I am asked all the time for assistance with home antivirus. Here are some free options:
Avast (I use this)
Microsoft Security Essentials (I use this. Yes... I run two antivirus programs)
Avira
Malwarebytes
AVG
Panda - Cloud and Free Tools
If you feel the need to drop money on antivirus here are some options:
Kapersky
Panda
Norton (I don't recommend it and I won't even link to it)
F-Secure
G Data
Last but not least, practice good browsing habits and back your data up with some level of regularity.
