Man, I hate to say it, but I would spend the $109 for a copy of OEM Vista Home Premium.
The benefit of this one I linked is that is comes with a free coupon to upgrade it to Win7 when it is released.
If you take it to a shop, they will charge you more than that to "fix" it. What they will do is use an OEM copy that they have and re-install it using the keycode on your computer. You still won't have a disc if something happens again, and I'd bet they will charge you more than the $109.
First download a copy of a "disc nuker. " I use Heidi.IE
(I know you'll have to use someone else's computer, but it will let you make a boot disc). I think most people use DBAN
(Darik's Boot and Nuke). Insert the bootable floppy in your floppy drive and let it run. It will erase everything on your hard drive and let you start over. Then install your Vista.
Remember, OEM means there is no free Micro Soft support, but their support is crap anyway. You are better off coming here and asking questions than asking Varkeneeth in Bangladesh, I mean calling MS customer technical (non)support.
Edited by DeathStalker, 30 June 2009 - 08:07 PM.