It is a Western Digital Caviar AC23200 3.4GB.
I booted into the BIOS and it shows it as Primary Master and 211.1TB!
Sometimes (not always) the POST will show this error:
Using DLGDIAG 4.15, I am running the Extended test now, the quick test was not available. The info in DLGDIAG shows just symbols, as can be seen here:
Corrupted hard drive by Tripredacus, on Flickr
As far as expectations, I expect the disk to have Windows 95 or 98 on it, and likely be FAT32. Everything I try to do that does anything with the disk is extremely slow. For example, it took 20 minutes or so to give me the menu in DLDIAG.
EDIT: Test completed. Code 0250. Can't find what this code means.
Final code 0250 by Tripredacus, on Flickr
What are the chances that I can access this data? What other tools/tests can I run?