(http://i60.tinypic.com/2h8aibq.jpg)
The Start screen should automatically be used on touch-centric devices; however, if you want to always use the Start screen, you can configure it to be used as follows:
1. Right-click the taskbar and select Properties.
2. Select the Start Menu tab.
3. Clear the Use the Start menu instead of the Start screen option, as the following figure shows.
4. Log out and log back in for the change to take effect.
source:windowsitpro