My computer has been infected by many viruses and spyware to the point of no return and has been partitioned many times. So now I have taken my computer back from my very irresponsible roommate and want to rewrite to zeros and start over. Can someone tell me how to do this? Oh yeah Im using Windows Vista Home Edition.

If you're absolutely, positively sure you can re-install from the CDs you have, then use DBAN to wipe it all clean.
http://www.dban.org/
If you're relying on a hidden recovery partition then exercise caution.
This is extreme "Do not pass GO, do not collect $200" territory!

Another idea is to put in a new hard disk (or borrow one) just for a dry run, to make sure you have any key drivers to hand.

Then erase the old one and use it for backup (or extra storage).

Just borrow an xp disk and use the format function on that or xp based bootable cd like UBCD and use that to run a FULL format, that should be more than adequate for your needs