If I go to Personalization > Window Color and Appearance I cannot make changes because I disabled something couple months back.
I cannot change the colors of Windows, Start Menu, transparency, color mixer, color intensity but I can change the color schemes but that doesn't change anything either.
If you see the Windows Aero theme to select, click that. If you don't see it:
1. Click on Windows Vista Basic and hit effects.
2. In the first drop-down list, click Standard.
3. Click OK.
4. Close it.
5. Open it again.
6. It should come up with a theme called Windows Aero. Click on it and hit OK.