3 possibilities I can see:
1. From the new admin account (did you succeed in making it ?), do a Windows Explorer
search for your files (they are there of course) and go through the "take ownership"
process. Post back if you don't know it.
2. Boot to a Puppy Linux CD and copy the files to external media or into a new account
from there - it bypasses all of Windows efforts to hide the files
3. Pop the HDD into a USB enclosure (they are very cheap) or into another PC (slightly
more fiddly) and get the files that way.