First thing to do is grab a SD card or Flash Drive or any form of portable storage that you can and get Super Anti Spyware and AVG from download.com aka cnet. secondly, install them onto your PC and keep the portables for back-ups. I keep my AVG set to auto scan my PC every morning at 4 AM - full PC scan. Super Anti Spyware you will need to run manually. After you first install them, restart your PC in safe mode without networking and let them run. Do one after the other, not at the same time. Restart again and you should be fine. Then just keep doing the normal scans on a regular basis.
Just to let you all know, I was a A+ certified PC Technician until September. Sick of working on PCs so I never renewed my certification.lol Regardless, if you have a question, hit me up.