One new feature of the taskbar in Windows 7 is thumbnail previews of multiple windows of a specific application. By default, there is a 400ms delay before the thumbnails appear. This can be easily changed. First, download the registry key I have provided below.
Download Change Hover time Registry Key here
By default, the registry key file is set to decrease the delay to 30ms. If you want to change this, you can right click the registry key, and click on Edit. In Notepad, you can change the number 30 to anything between 0 and 4000. I don’t recommend choosing 0 for the delay. Once you’re done, save the file and double-click it to add the key to the registry. Changes don’t take effect until you restart your computer.
Manual Method:
You can also edit the registry key manually yourself.
1) Open the Start menu and type regedit in the search bar
2) Proceed to the following directory: HKEY_Current_USER\Control Panel\Mouse
3) Right click the MouseHoverTime key and choose Modify
4) Change it to a value between 0 and 4000. The number you input will be the millisecond delay before thumbnail previews activate when you hover your mouse over an application.I don’t recommend selecting a value of 0 for this option.
Changes don’t take place until you restart your computer.
