#1- Back up your data to external HD.
#2- Format HD.
#3- Reinstall operating system and applications.
#4- Install Antivirus software.
#5- Scan external HD before moving data back to internal HD.
#6- Keep your operating system and AV updated and stop going to porn sites and 1-5 probably won’t be necessary in the future.
Better still:
Download latest cd image of Ubuntu linux. Burn to a CD.
After backing up your windows HD, install Ubuntu. Use Wine to run essential Windows apps (except for games, most will run better under Wine than under Windows.)
Forget about _almost_ all malware and viruses.