Themes have been a part of Windows since at least Windows 95, and they're still with us in Windows 7 in the form of a single file that packages together one or more desktop backgrounds, a screen saver, a window border color, a sound scheme, desktop icons, and mouse pointers. Windows 7 comes with a handful of themes, but it also lets you get more. In this guide, we're going to show you how to unlock themes that are already on your computer, remove themes that you've added, and get more themes online.
Introduction
To change themes, you'll need to get to the Personalization window. Right click the desktop and click Personalize, or type "change theme" into the Start Menu and hit enter. Alternatively, you can find the right applet in the Control Panel—if you're in the category view, under "Appearance and Personalization" click "Change the theme," or if you're in one of the icon Views, just choose "Personalization".
Windows 7 typically comes with about 13 themes:
• Aero Themes: Windows 7, Architecture, Characters, Landscapes, Nature, Scenes, and your country's theme
• Basic and High Contrast Themes: Windows 7 Basic, Windows Classic, High Contrast #1, High Contrast #2, High Contrast Black, and High Contrast White
In addition to your country's theme, depending on the Windows 7 language you have, the installation may also contain additional themes. For example, the English version of Windows 7 contains five themes: Australia, Canada, South Africa, the UK, and the US. Depending on what English region you chose during the installation of the operating system, though, only one of these will be visible in the Personalization window; the rest will still be installed, but they'll be hidden by default.
Unlocking themes
We've broken down the process of unlocking the hidden themes into three easy steps:
1. Unhide the relevant files
Summary: Folder Options => View => Advanced Settings => Hidden file and folders => Select "Show hidden files, folders, and drives" and uncheck "Hide protected operating system files (Recommended)"

To open Windows Explorer, either hit the Windows Key + E or open any of the folders links in the Start Menu. Once there, click the Organize drop down menu in the top left and choose "Folder and search options." A faster way to do this is to type "folder" into the Start Menu and hit enter.

You are in the General tab now, so switch to the View tab up at the top. Once there, look at "Advanced Settings" in the lower half of the window, and under "Hidden files and folders" select "Show hidden files, folders, and drives." Three options below that, make sure to uncheck "Hide protected operating system files (Recommended)."

If you get the following prompt, click Yes. Hit Apply and close the Folder Options window.
2. Apply and save the theme
Summary: Navigate to "%WINDIR%\Globalization\MCT\" => Open one of the region's folder => Open the theme folder => Double click the file inside

If you still have Windows Explorer open, type "%WINDIR%\Globalization\MCT\" (without the quotes) into the address bar and hit enter. You can also put this into the run dialog box (Windows Key + R) or into the Start Menu and it will work fine. If you're wondering about the "%WINDIR% part, it's equivalent to typing in C:\Windows but it will work regardless of what drive letter you have the Windows folder installed on.
Once you're in the folder, you should see at least one country-specific folder. if you're using an English version of Windows 7, you'll see MCT-AU, MCT-CA, MCT-GB, MCT-US, and MCT-ZA, for the five regions we mentioned above.

Open the folder that corresponds to the country you don't have already have the theme for, open its Theme folder, and double-click on the .theme file inside.

Your Personalization window should pop up, you'll see the theme applied, and it will be saved there. In the screenshot above, you can see our Personalization window after we added the remaining four themes that we were missing.
3. Cleanup
Summary: Windows Explorer => Organize => Folder and search options => View => Select "Don't show hidden files, folders, or drives" and check "Hide protected operating system files (Recommended)"

This is pretty much just step one reversed. Type "folder" into the Start Menu and hit enter. Select the View tab. Under "Hidden files and folders" select "Don't show hidden files, folders, and drives" and check "Hide protected operating system files (Recommended)."
Official themes
Back in January 2009, during the Windows 7 beta program, Microsoft launched the "Personalize your PC" webpage, which has since been changed to the Personalization Gallery. At the time, the site had 15 themes, 13 desktop backgrounds, 8 desktop gadgets, and 5 SideShow gadgets. Now, Microsoft is offering 34 themes, 23 desktop backgrounds, 3647 desktop gadgets, and 35 SideShow gadgets. The gadgets are actually now available at gallery.live.com, but since they're not part of a theme, we'll leave them for another story.
The 34 themes available for download are broken down into two categories. Here is how your My Themes section should look if you decide you want every single one:

• 14 Feature Themes: Avatar, Bing's Best, Happiness Factory, Ducati, Ferrari, Gears of War, Gears of War 2, Infiniti, Lugares Coloridos, Refresh Everything, Porsche, Zune Characters, Zune Elements, and Zune Zodiac
• 20 International Themes: Australia, Brazil, Canada, China, France, Germany, India, Italy, Japan, Korea, Mexico, Netherlands, Poland, Russia, South Africa, Spain, Taiwan, Turkey, United Kingdom, and United States

Getting the theme on your computer is as simple as clicking Download, clicking "Open," and then agreeing to any security prompts Windows might throw at you. Just as with the hidden themes we described above, the theme will automatically be applied and saved in the Personalization window. Sharp-eyed readers will notice that for whatever reason, the country themes that are on the Personalization Gallery website are not the same as the ones already included in a Windows 7 installation that we unlocked at the start of this guide. So yes, it's worth getting both and deciding which ones you prefer.
Creating Themes
Creating a theme in Windows 7 is not as daunting a task as it may seem. It's actually pretty simple, assuming you aren't planning to create one from scratch. You just have to pick a theme that you already like, and then simply change one or more of the following: desktop backgrounds, window border color, sound scheme, screen saver, desktop icons, and mouse pointers. Remember, a theme is just a package of all these elements. We've split each of these groups into a separate step. Each step assumes you're already in the Personalization window (Right click the desktop and click Personalize).
Before you get your hands dirty, pick a base theme (the Windows 7 theme is a good start). Notice that right after you make the first change, a new theme will be created with the name "Unsaved Theme." Despite its misleading name, every change you make is actually saved, and you can switch between it and other themes just like any other. You won't be able to create a new custom theme, though, until you save the current one, and your unsaved theme will remain at the top of the list until you finally do give it a proper name.
1. Choose desktop backgrounds
In the Personalization window, click on "Desktop Background" (the first option at the bottom).

From here you can see all the backgrounds Microsoft has included in Windows 7 (they are located in "%WINDIR%\Web\Wallpaper").

As you can see, there are a few different categories of desktop backgrounds in the "Picture location" drop-down menu. If you want to use your own backgrounds, click on the browse button on the right-hand side, and navigate to the appropriate folder to add them.

You can pick as many backgrounds as your heart desires. To select the ones you want, click the checkbox in the top left of every background image. The checkbox only appears when you mouse over the image.

You can also choose the picture position (default is Fill, and you'll likely want to leave it at that unless you're using a small image). Finally, if you choose more than one background, the remaining section will no longer be grayed-out and you will be able to choose how often the wallpaper changes, whether the wallpapers should change in the order you've selected them or randomly, and finally a power-saving option if you're on a laptop. Once you're done, click the "Save changes" button in the bottom right.
2. Choose a window color
In the Personalization window, click on "Windows Color" (the second option at the bottom).

This color will affect your window borders, the Start menu, and the taskbar, so choose carefully. You can pick from one of the 16 presets, or you can customize further by clicking on "Show color mixer." You can also turn transparency on (checked) or off (unchecked).

If you play around with these (move the sliders left or right), you can achieve very good results (the changes will appear on the fly). You can get quite vibrant and solid colors, as well as decent shades for a less distracting look. The settings in the screenshot above will give you a very dark black.

The "Advanced appearance settings..." link will open up the "Window Color and Appearance" window that you're used to from old Windows versions. In it, you can tweak a lot more elements of the Windows UI. When you're done, click OK, and then click Save changes.
3. Choose a sound scheme
In the Personalization window, click on "Sounds" (the third option at the bottom).

Here you can choose a sound scheme from the drop-down menu: Afternoon, Calligraphy, Characters, Cityscape, Delta, Festival, Garden, Heritage, Landscape, No Sounds, Quirky, Raga, Savanna, Sonata, and Windows Default. Notice that you can also turn the Windows Startup sound on (checked) or off (unchecked).

No matter what sound scheme you choose, you can select a different sound for any of the program events in the list. Just click on a program event, and then in the Sounds drop-down menu, pick something else. You can play it back to hear how it sounds using the Test button, or you can pick your own sound by clicking on Browse (only .wav files are accepted). In case you're wondering, "%WINDIR%\Media" is the location that Microsoft chose for all the Windows sound files. Notice that when you make a change, the word "(modified)" will be added to the name of the sound scheme. Unless you hit Apply, your changes will be lost.

If you click "Save As," though, you'll be able to give your customized sound scheme a new name and save it. The Delete button is greyed out, unless you want to delete a sound scheme that you created. Once you're all done, hit OK.
4. Choose a screen saver
In the Personalization window, click on "Screen Saver" (the fourth option at the bottom).

Here, you can choose one of the following screensavers: (None), 3D Text, Blank, Bubbles, Mystify, Photos, and Ribbons. In case you're wondering, "%WINDIR%\system32" is the location that Microsoft chose for storing all screensavers. If you want to add one, you'll have to drop it in that directory (and then close and reopen the Screen Saver Settings window).

Certain screensavers have options you can tweak (choose a screen saver and click on the "Settings..." button) but others don't have any, and you'll get the above prompt if you try to click on the button. You can also hit Preview to see the screen saver before choosing it, set the delay time for how long the PC should be inactive before the screen saver shows up, and whether you want to display (checked) or not to display (unchecked) the logon screen after the screen saver is turned off.
5. Choose desktop icons
In the Personalization window, click on "Change desktop icons" (the first link below "Control Panel Home").

Once there, notice that you can choose to allow themes to change your desktop icons (checked) or for themes not to affect desktop icons at all (unchecked). You can also add or remove five of the most basic icons on the desktop (Computer, User's Files, Network, Recycle Bin, and Control Panel). Only the Recycle Bin is visible (checked) by default. You can't change the Control Panel icon, but you do have the ability to change all the other ones, including the empty and full Recycle bin icons.

Select the icon you want to change, and click on the "Change Icon…" button to see a list of images to choose from. Once there, you can also click on Browse to add your own icons. Windows will accept .ico files, but it will also let you look in .icl, .dll, and .exe files, which usually have icons embedded in them. Once you select your desired icon, click OK. You should see the icon change in the "Desktop Icon Settings" window. You can always hit the "Restore Default" button if you change your mind. Click OK when you're done.
6. Choose mouse pointers
In the Personalization window, click on "Change mouse pointers" (the second link below "Control Panel Home").

Here you can choose normal, large, and extra large sized mouse pointers of the following styles: Windows Aero, Windows Black, Windows Inverted, and Windows Standard. Pick one of them as your base. You can then change any of the different pointers by clicking on one of them, and choosing Browse. Again, Windows will show you a couple it already has (located at "%WINDIR%\Cursors") and will also let you use your own (.ani or .cur).

Once you've made all the changes you want to, click on "Save As" and pick a name for your mouse pointer scheme. Again, you can only delete the custom schemes you create.
Saving Themes

Once you've set up all the elements of your new theme the way you like them, you'll want to save your work. You don't have to save, but if you make any changes to the theme by accident, you'll have to revert those changes manually. Plus, it should have a proper name, don't you think? Right click on it, and choose "Save theme."

You should get the above "Save Theme As" window. Choose a name better than "My Theme" and you're good to go (custom themes you create are placed under "%USERPROFILE%\AppData\Local\Microsoft\Windows\Themes").
Sharing Themes

Saving a theme will save it for use on your computer (.theme), but you have to actually choose "Save theme for sharing" if you want to move it to another computer (.themepack). After right clicking on a theme and choosing this option, you will be able to save the theme as a .themepack file.
Removing Themes

If you're not already there, get to the Personalization window (right click the Desktop and click Personalize). Then, right click on any theme in the "My Themes" section and select the only option in the drop down menu (as seen in the screenshot above): Delete theme. You can only right click on themes that you have yourself added: all other themes will not have anything in their right click menu. Also note that if you are right clicking the currently active theme, there will not be a delete option.
Conclusion
We hope this guide has helped you understand all the theme support Microsoft offers in Windows 7. If there's anything else you'd like us see add to the guide, please let us know in the comments!
source:arstechnica