Long answer:
Before turning it back on use a different computer to go through all of her online accounts and change the passwords. ALL OF THEM! (Email, Skype, Bank and Credit Cards)
If it has a DVD drive you can try booting from a Kaspersky Rescue Disk (http://support.kaspersky.com/us/viruses/rescuedisk) to try and remove things they might have installed.
After doing that I'd boot it into safe mode with NO Internet and copy her files to a USB stick. You might be able to do that from the Rescue Disk tool interface -- I can't remember.
Then you can try booting her PC up normally (but without Internet access still) to run whatever anti-virus she might have installed, but mostly just to see what happens and to make note of what software she has installed.
Gather up all of that software and reinstall it. Completely. (Format the harddrive)

Sorry.