Killing wml.exe

Gidday, first time user looking for advice.

I have an XP Pro machine that got wml.exe. Unfortunately it messed with the Windows XP registration, and I cannot for the life of me find the XP sticker with the license code. I got half way through the malware removal steps on MajorGeeks, but then I cannot get back in to finish off since the Genuine checker is locking me out. I got as far as Malwarebytes but couldnt get log files off since I'm locked out. SAS and Malwarebytes both showed wml.exe on three files.

So, rather than try to chase my computer construction and/or Microsoft, I'm thinking I just format the drive and replace with Windows 7 (about time I upgraded anyway).

Q1 : Will a format of the C drive get rid of wml.exe?

Q2: Is there anything I need to pay attention to when I install Windows 7 to make sure wml doesn't survive?

Q3: I've got two other drives on the machine, one with media, the other with games. When I ran SAS and Malwarebytes, it didn't show any problems on these drives. I'll kill the games once I get the machine up and running, but the media (music and videos in AAC and MP4 format and the like) I assume is going to be fine?

Thanks for the help guys. I must say that although removal of malware is long and painful, the guides you've created are astoundingly good considering the level of information needed to be communicated. I cant speak highly enough of the service!