T21 thinkpad win 2k freezes normal mode bootup

hi,
my ibm T21 P3 800MHz with win 2000 pro. sp4 freezes in normal mode. the safe mode works fine. it has 256 Meg ram and 20Gig hd.

while booting in normal mode the blue status bar (titled: starting up) of win 2k pro. freezes and does not move.

it started doing this after my young nephew somehow logged into as Admin and messed it up about three months ago.

Please help? regards, hussnain