Help!!! Windows 2000 Start bar

i recently downloaded pc accelerator to my win2k system and upon installation i was required to reboot, however, when i rebooted my start bar was completely frozen, windows tabs, start icon, everything just stopped working...i tried to uninstall pc accelerator, and bar is still frozen, someone help!!! my system is not that fast at all (600 Mhz) so to have all these windows open at once really doesnt do anything but slow me down but i can't minimize or they wont come back up...anyone have any idea what this is caused by or a similar problem with pc accelerator please give me some insight...