To switch between themes, Changing the Look of Windows Vista on Your Screen
In Control Panel, click Appearance and Personalization.
Under Personalization, click the Change the theme task.
Click the Theme arrow, and then in the list, click the theme you want to use.
Then click OK.
To adjust the refresh rate and the color depth of your monitor, Optimizing Visual Effects
In Control Panel, under Appearance and Personalization, click the Adjust screen resolution task.
In the Display Settings dialog box, click Advanced Settings.
In the Advanced Settings dialog box, click the Monitor tab. In the Monitor Settings area, click the Screen refresh rate arrow to display a list of valid refresh rates for the selected monitor.
Select a screen ...