Windows XP Pro has a great program called Group Policy Editor that allows system administrators to modify the settings to a great number of windows features. TO start the program up follow the directions below.

1. Open the Start menu and click Run
    
2. Type gpedit.msc and click OK
    
3. The Group Policy MMC appears
    
4. Click through the different nodes of the tree to see all the hidden features of Windows XP that you can edit without touching the registry.

Examples: Changing IE displays, Clearing the pagefile at shutdown, boot-time defrag settings, and many many more.

Another tip is to add this to your Administrative Tools by adding the shortcut to gpedit.msc.