I have found that about 1 GB of restore is equal to about 6 months of system time.
Since you had 90Gb allocated, that should be good enough to take you back to 1933, well before your problem.
Its kinda funny, I just answered this in another thread yesterday, but that guy never came back on - so I guess he fixed it on his own.
Since you have a lock up prob, I assume you really dont want "normal old XP" restore.
(all programs/accessories/system tools/system restore)
So, what you do is tap F8 key during boot, get to the safe mode options black screen with the word safe in white in four corners, and pick safe mode with command prompt, enter
After the welcome screen starts, you pick Administrator and click it.
Then you will have DOS type cmd.exe window that will say something like this (from my memory)......
C:\>documents and setting>administrator***>
You then type this CAREFULLY [goes after the administrator>]
%systemroot%\system32\restore\rstrui.exe
and hit enter
after a bit of hesitation, the restore window will appear like magic.
rstrui obviously stands for restore user interface
a very little known handy life saving trick
Edit: note that rstrui has six letters