Answers: Avast:
http://www.avast.com/eng/download-avast-...
you could acquire Norton from google
http://pack.google.com/intl/en/pack_inst...
Seconding AVG anit-virus.
They save me more than once.
They do a check up on your computer every time your turn it on.
Love it.
Don't trust any free anti-virus software
I have free anti-virus software once and I get approaching 6000 virus at ONCE! The computer-fixer woman have to reset my comp
I use this one:
http://www.avast.com/
Works as resourcefully, save better than Norton.
AVG works for me.