When you place your mouse cursor over the taskbar button of a running application, a small thumbnail of the application will appear. By placing your cursor over this thumbnail, you will see a live preview of the running application and all other applications that are running will become transparent. If you find this feature to be annoying, you can disable it by following these steps.
1. Click the Orb (Start Button).
2. Go to the Search programs and files textbox and input regedit.
3. Select regedit.exe from the results.
4. When the UAC prompt appears, click the Yes button.
5. In the left pane of the Registry Editor, go to (and select):

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced
6. Right-click in the right-pane.
7. Click New and select the appropriate DWORD for your system.
8. Name the new DWORD DisablePreviewWindow.
9. Double-click the new DWORD.
10. In the Value data textbox, input 1.
11. Click the OK button.
12. Restart your computer for the change to take affect.
