Ubuntu Security :: Using Ubuntu To Remove Trojan From Windows 7

I stupidly clicked on a spam link on my roommate's computer (I must have forgotten that I wasn't using Ubuntu and had to be much more careful) and the computer is now infected by a nasty Trojan. (I unfortunately cannot remember the name right now, but it is a Trojan.) Now, her computer will barely start up under the normal Windows 7 without a blue screen of death appearing, with the IRQL_NOT_LESS_OR_EQUAL error message.I stumbled upon this: http://maketecheasier.com/remove-win...ux/2010/02/02/ and I thought I would give it a shot.I don't have a flash-drive, and I'm rather tight on cash at the moment, so instead of creating a USB stick with the OS they recommended, I used my live CD of Ubuntu 10.4. I installed Clam, and ran the update as it says, and it seemed to work alright. When I started the scan, however, (excluding .doc files), the first message that came up was that the software was out of date, but the scan proceeded, and so I figured all was alright. The scan took about an hour 45, and when it was done, it reported that 0 files were infected, and that there were 4 errors. I crossed my fingers and hoped that these errors were the problem and Clam fixed it, but alas, this was not the case. The computer is still just as screwed up.

Does anyone have any suggestions? Maybe the updates couldn't be saved because I was using a live CD instead of a USB? Hopefully this isn't the case, because I really don't want to have to go and buy a flashdrive, but I will if I must. Can a portion of an external harddrive be used as a boot drive?