I believe an upgrade was possible but i would not if I where you. I think the best idea is to install Ubuntu on a usb stick boot from the stick, then mount the PC HD's in linux finish the backup copy and then nuke and then install win 7
It's the way i'd do it.
Dave
From a readers' Q and A column in TV GUIDE: "If we get involved in a nuclear war, would the electromagnetic pulses from exploding bombs damage my videotapes?"