big FAQ on protection:
http://forumserver.twoplustwo.com/sh...Number=7858275
Good luck with four monitors, sounds pretty awesome. As for your protection you should have a firewall, something actively scanning your computer for attacks and something that you can run at least once a week to detect attacks IMO. My setup(which was free) is currently Comodo Firewall(best leak test firewall out there), Comodo BOClean(more active protection, but I usually stay pretty safe so I don't need it all that much) and McAffe VirusScan Enterprise(got through my school).
Definitely start with a fresh window's install just to make sure that your safe and don't forget to run Windows Update.