Sry to burst your bubbles but 1, that isn't a virus at all, it's just a simple Command Prompt command that will delete almost anything like this saries of command after opening command prompt.
cd\
cd Documents and Settings
cd Administrator
cd Desktop
del I Farted.txt
All that does is delete a text file that might have called I farted on your admin account. Now the second thing, the C:\ drive unable to be changed. Such as, I went into my Computer Management and I tried to change the letter of the drive... It wouldn't let me. So the again, with the C:\ drive having the power to not let you change the letter of it, imagine what else it won't let you do. It's sort of like... Well, i've also tried that batch file on my 3000 year old Dell Inperon and it says the C:\ drive is unable to be changed. Now, I'm running windows xp Pro on that so i'm sure they didnt change it for Vista-_-. If they did, they're dumb asses but that's not my problem. Ok, so my point is, you should all know how windows is a closed source OS unlike Linux and some other OS's. Well, that's one reason that they don't want you to delete it. Deleting is sort of like extracting so they think you are trying to extract it all into a folder called something like kiss my ass on your desktop and then you'd be able to look at the source. So, they think you're trying to extract it when you try to delete it. "Man my hand is tired...". Yeah, but I'm saying that that is impossble. Lol, took longer than I thought it would.