Infected computer

Heres the situation, I have a computer that has windows files that have been ''patched'' by Viruses.
I ran a scan with avg and it came up with many Patched.FS files I click remove all unhealed and nothing happens, I've tried different antiviruses but theres no way I can use the other viruses since my computer wont let me uninstall avg and other av's + avg = no good. More things to mention: my cd/dvd drive was busted by my little brother, and running command prompt doesnt work.

When I try to do system restore the farthest I can go back is January 2011 and my computer was still infected back then
Help? :]

Loose guide on how to install from USB Drive, providing you has one. :3

1) Find out which version of Windows you have (Starter, Premium, Ultimate, etc) and weather or not it's 64 or 32 bit (Skip if you have a pirated copy)
2) Find your key to your copy of Windows (Skip if you have a pirated copy)
3) Download an .iso off a torrent site, or perhaps if you have a key, from Micosoft (Not sure if you can do this)
4) Get 4GB USB Thumb Stick (Following this quick guide on how to get the usb ready)
5) Extract all the iso contents to the drive
6) Change you BIOS boot order so the thumb stick will boot before anything else
7) "Press Any Key to Boot from blah blah" and follow the prompts