Vista - Locked Partition

Hello, I'm new to this board and currently trying to look for a solution to my problem
Hope experts/anyone can shed me some light.

- My computer has multiple partitions
- C: contains VISTA 32bit
- D: contains XP (on another HDD)
- E F G are just documents and files

- Under VISTA, there are user accounts for me and my roommate
- I'm the admin to the PC and was able to limit accessibility to partition E to my VISTA account only and to VISTA OS only.
ie. my roommate cannot access to E drive and no XP user can access this E drive either.

I encountered some issues recently and must reformat my C:. So the question is, when I delete my VISTA and reinstall a fresh copy, will I loose accessbility to drive E afterwards? (since the linkage from the account before is now gone)

My VISTA is pretty corrupted at the moment (I think a lot of registry files are gone after I used that check disk utility). VISTA is corrupted such that I cannot log back into any account. But the files seem to be there; it's just that registry are pretty screwed.

What can I do to "unlock" drive E now so XP can access it?

I have been searching for so long for a solution...thanks in advance