Easy peasy way to fix this:
1. Get a Windows disc, not torrented, 100% legal, just in case.
2. Do a full format on your hard drive(s).
3. Get a cup of coffee and wait for it to format.
4. Install Windows after it formats.
5. Once you install that, install Avira, AVG, or Avast.
6. Get firefox, get Noscript, stop browsing porn sites.
7. ???
8. Profit!