This
is a trick extremely useful if you hate that, when Windows Update is
executed, it prompts you to restart your computer continously (every 10
minutes).
Do you remember the dialog box "Updating your computer is almost
complete. You must restart your computer for the updates to take effect. Do you
want to restart your computer now?"? You've only the choices to Restart
Now/Restart Later, and Restart Later means after 10 minutes. It's a too
short delay I think.
The trick to change this setting can be done by using Group Policy Editor
like explained below (you need XP SP2):
Start / Run / gpedit.msc / Local Computer Policy /
Computer Configuration / Administrative Templates / Windows Components / Windows
Update / Re-prompt for restart with scheduled installations
Here you can choose your new delay time (for example 1 hour or two, the right
for your needs). Obviously, in order this setting to make effect, you need a
system reboot and after that the new delay is registered. 