Windows Win2K can't Boot-up

Hi,

Can anybody tell me why my "microsoft windows 2000 professional" can't boot-up?

i have,
microsoft windows 2000 professional in 'c' drive and
microsoft windows xp professional in 'd' drive.

When i choose win2k in the initial boot menu, it shows the booting progress bar, completes it and also shows the blank desktop and mouse pointer. Few seconds after that, when its time to show the desktop icons, start-up menu and the task bar, everything disappears and the computer restarts on its own.:mad:

i am able to boot winxp and its working fine.:) my ‘boot.ini’ file is all fine!!! here are its contents.

*******
[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(2)\windows [operating systems] multi(0)disk(0)rdisk(0)partition(2)\windows="microsoft windows xp professional" /noexecute=optin /fastdetect
multi(0)disk(0)rdisk(0)partition(1)\winnt="microsoft windows 2000 professional" /fastdetect
*******

please help. Thanks in advance:)