Sooooooo I have all of my computer parts ordered and Virus protection has totally slipped my mind! GAH! So like every gamer, I would like the best Anti-virus software that doesn't bog down my computers speed when i'm doing basic tasks and gaming.
It used to be that Kasperski was the only one i'd recommend anyone pay for. These days they are all just about as good (or bad) as all the other ones. Even though they all perform roughly the same having one (any one) is better than not having anything.
Until last year I was using AV Software like AVG / avast ...
The reason I stopped using AV Software (besides Common Sense 2013 :p) is because I never had any alert, except some programs that I already knew that they were most likely infected.
So if you'd like to have that extra feeling of pseudo-"safeness" install ANY Antivirus-software, it really doesn't matter.
What you can do on the other hand is to use script-blockers for you browser (Noscript for Firefox for example, Notscripts for Chrome I think it's called) that won't load any script unless you want it, this is were Common Sense comes in. You can allow important scripts via click for your trusted websites, so that you won't need to unblock these scripts everytime. So it is a one-time investment that you make (making the websites you trust work and allow their scripts to run).
If that's not enough you could run (in addition to script-blockers) your browser in Sandboxie, that should really protect your gates to the internet.