The most common Antivirus Tools out there right now would be Norton or McAfee well these do the job but I found a program does better (I think). It is called Kaspersky.

Norton AntiVirus:
www.symantec.com

McAfee AntiVirus
www.mcafee.com

Kaspersky AntiVirus
www.kaspersky.com

Try it out and post what you think. No real fancy graphics but it is awesome in it's scanning process.