Here's how you can set up a restart button on your desktop:
1. Create a shortcut (Right-click on desktop, select New > Shortcut).
2. For location, type the following:
shutdown -r -t 0
3. Click Next, enter a name for the shortcut ("Restart" is appropriate), and click Finish.
When you click your Restart shortcut, Windows XP will reboot *automagically*!
The "-r" switch tells XP to reboot. If you'd like the shortcut to shut off your PC instead, change it to "-s"; to simply log off, change it to "-l". The "-t 0" sets the timeout (in seconds), so up this value if you find the need for it. To force running applications to close, add "-f" -- be careful with this one!
For more information on Shutdown, type "shutdown" in a command prompt window (Start > All Programs > Accessories > Command Prompt), or search for Shutdown in Windows XP's Help and Support Center.