Mac mini Hard Drive dead? please help

I took out my Mini's 40 gig hard drive and replaced it with a 60gig 7200 rpm hard drive i put the 40 into an external usb2.0 enclosure... i'm trying to get all of my data off of the old hard drive and copy it to the new on that's in the computer now... when i try to copy some files the computer will freeze. i went to disk utility and tried repair on it and i get this:

Repairing disk for “Backup HD”
Checking HFS Plus volume.
Checking Extents Overflow file.
Checking Catalog file.
Checking multi-linked files.
Checking Catalog hierarchy.
Checking Extended Attributes file.
Invalid leaf record count
(It should be 1 instead of 1405)
Checking volume bitmap.
Checking volume information.
Repairing volume.
The volume Backup HD was repaired successfully.

Repair attempted on 2 volumes
1 HFS volume repaired
1 volume could not be repaired

i scanned with techtool pro 4 and i get no errors at all everything passes... i'm gonna try to swap the hard drives again but if that doesn' work i might just have to check out drive savers becasue i need the data off of that hard drive.... it had all of my pictures and music and so much important data... i've swapped hard drives many times.. i replaced the one in my iBook and i never had this problem at all.... any suggestions????

i was actually running the os the mini came with 10.3.7 and no luck and i just updated to 10.3.8 still no luck, formatting isn't an option cuzi want the data off of the hard drive.. i think i'm gonna try puttin it back in the mini again...... unless there are any other ideas???