I almost forgot...if you're going to use Bittorrent, get PeerGuardian2 first. Spend a day or so learning how to use it and THEN get bittorrent. PG2 is essentially a blacklister. It's like a firewall that blocks a lot of adware, spyware, and tracking companies like BSAA and BayTSP by identifying their IP address and refusing connection to your computer. If a site you like is blocked, you can simply unblock it permanently or allow it for either 15 minutes or 1 hour. It's saved me a lot of headaches and angry emails from companies...if I downloaded stuff...which I don't.

If you're not downloading anything, you can simply leave it off and surf like any other day. Hard to beat seeing as how it's free and it's open source code so it's always being improved.
Oh...and don't use the old Methlabs.org link. Go to the one on Sourceforge.