There's a setting in XP where, if the OS detects an error causing it to shut down, it will automatically re-boot. There may be a clue here.
There might be a slight glitch during the shut down wanted; maybe its the kind of glitch that you wouldn't normally know about or care about. But XP will care about it if it has the wrong setting. So follow this trail:
Open System in Control Panel.
On the Advanced tab, under Startup and Recovery, click Settings.
Under System Failure, select the check boxes that correspond to the actions you want Windows to perform if a Stop error occurs:
1.
Write an event to the system log specifies that event information will be recorded in the system log.
2.
Send an administrative alert specifies that your system administrator will be notified.
3.
Automatically reboot specifies that Windows will automatically restart your computer.
I've just realised that I've duplicated some of the info in BOAC's link. Mine was from a different source - still MS - but it didn't mention EZCD Creator.
I'll leave mine in case some readers have set-ups that don't follow links.