Have a look at this click here There's a link in the left pane for WinXP.
Also, you can speed up the closing of WinXP. Run regedit and navigate to registry key
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet and click on the Control folder.
Look for WaitToKillServiceTimeout, right click it and choose Modify. Change it to something less, say, 1000.