the trick with slaving is that you need a second PC. you take your hard drive out of your PC and plug it into someone else's - then you can access it as if it was just another file on their PC. there are plenty of walkthroughs for this on the net, just make sure it is all nplugged from the wall first, and remember that all the cords etc can only physically be plugged on one way, so you should be fine. there are two types of hdd connectors, so yo will have to find the right type of PC. Pata or Sata. then grab everything off the PC and back it up while you can.
run AV over it as normal, along with chkdsk (start-my computer-<rightclick your drive>-properties-tools tab-error checking, select both boxes, then ok,ok, and manually restart your PC)