NT 4.0 Win2000 Dual Boot

Thinking naively, I just installed Windows 2000 Professional on a seperate partition.
I have SP5 on my NT 4.0 Workstation.
The install went fine, after I rebooted, I checked out 2000 for a little while, then it was time to get back to work. So I chose NT 4.0 Workstation from the prompt, saw the Bootloader screen, then “IT” happened. The laptop that I have rebooted. After many tries, I am unable to boot into NT 4.0, I can see the C: partition (NTFS), (Thank God, I just copied all my data to the Network)but I can’t boot into it. I thought I did everything right. My Windows 2000 files are on the D: drive which is FAT.

HELP!!