it could be a memory problem, or virus
is this spybot download compatable with win2k ????
was the reason you are downloading spybot because you have a virus/malware problem
you could try running memtest
download UBCD4win
http://www.ubcd4win.com/
you will need a working PC and CD writer and a CDR
download the ISO
right click on it and Burn onto a CD
now boot this CD - it has lots of tests on it - including memory test
have you run a virus checker on the machine