Your idea for a second drive is a good one, but if he boots into win2k, he might not be able to access the data , NTFS permissions are funny that way. What he should do is boot from a live Linux CD, mount the hard drive, and then copy everything in the "documents and settings" folder to either a CD, another partition on the hard drive, a second hard drive or an external drive of some kind (flash drives are in gigs of capacity these days)
Then he should try to re-set the adminstrator password. there are ways to do this with Linux.
Recover Administrator's password
Thats the best howto I could find after searching for a few minutes, but there are more options if some one is willing to dig.