Right click on My Computer, there is a System Restore tab, check the box that says "Turn off System Restore on all drives" before you scan/edit/reboot, and turn it back on only AFTER you've made sure you're clean. As for safe mode, hit F8 after the bios post screen, but before the XP loading screen. I'm not sure if restoring an old config would work as the file would still be on your computer and you'd probably be vulnerable to the worm again.
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It takes 43 muscles to frown and 17 to smile, but it doesn't take any to sit there with a dumb look on your face.
I have fun. Usualy at my own expense, but I have fun regardless