I am currently using norton 360 for my computers around the house, it offers good protection, and does now use much resource. It also is probably the best one that doesnt seem to affect start up time for me, while the others gave really bad start up times. Norton 360 offers everything from virus definitions, computer firewalls, online backup storage accounts, and defrag and cleaning features that happens automatically. That means no more having to remember to clean and defrag your computer ever so often. Norton 360 will do all that, I have yet to experience any problems or any viruses passing through to my system. More and more ppl are using anti-viruses other than norton as well, because I guess of there bad experiences with previous norton programs, but some of the other anti virus programs that they go after is mcaffee, pcillin, and a couple other programs that have fallen out of my memory unfortunately. But if you looking for a reliable program to use to protect your computer I would highly reccomend Norton 360 for your system and home.