Edit: So right now she's got AVG running. Didn't even have a virus scanner up to this point, but it almost instantly picked up two files. "onoes.exe", and "outlook.exe". Strangely enough though, tried running it under safe mode at first, which caused the computer to turn off, and impossible to turn back on unless you held the power button just so.
But I told her to let the virus scan finish, and after that, I plan on running Adaware, then AVG's anti-rootkit thing, followed by deleting a whole bunch of folders that are just in the root of her hard drive, with what look like a single update file in each and every one of them, then uninstalling all the programs she doesn't need.
And what's more, in her "Shared" folder, there were a whole bunch of zip files, all 196KB, and all with very, how to say, "general" names. Things like something about eBay, EasyPHP, EasyHTML, and so on. Strongly suspected them of either containing viruses or having been downloaded by a virus, so they've all been deleted.
Just... wow. Dad's computer's cleaner than hers, although he also uses his for far less compared to her. At the moment, just for recording things for his radio class, and sending them off to whoever needs to review them.