Yes, its really annoying. Even turn on/off button on my PC won't turn it back on, I have to unplug my PC from wall jack, in order make the button work or turn back on. My system restore is turned off, hope you remember that fix. Speaking of the power button, could the cause be in the BIOS?
yes - nearly mentioned that - but it is quite unusual for an app install to affect your BIOS settings! However check them out and report back... again....
 oh yeah and consider turning back on your system restore? You can always reduce the amount of disc for it if that is a problem to you[/edit]
You may be having a critical error during shutdown which causes XP to reboot.
Right-click My Computer > Properties
Click the Advanced tab and then click the Settings button found in the Startup and Recovery section. Untick the Automatically Restart check box so if it is a critical error causing the reboot you will see the error message. The message may be in event viewer too.
Ep, glad to see you come back and tidy up...did want to ask a one day favor, I want to enhance my resume , was hoping you could make me administrator for a day, if so, take me right off since I won't be here to do anything, and don't know the slightest about the board, but it would be nice putting "served administrator osnn", if can do, THANKS