does your computer have a virus checker on it ?. sounds like you either have a boot virus or you have deleted a major file . may want to wipe the system and restart.if a virus checker is in place.
1. are you able to go into safe mode??
ie just after the bleep (post noise )press f8 or f7
that should take you into safe mode, then run you virus checker.
2. if no virus found , whilst in safe mode use system restore go back to a point were you know the computer ran ok
smithers
November 2005