This is a bit of a late entry but I've been using McAfee now for a coupler of years both at home and I look after it for my company and I've never had any major dramas. They have also just released a desktop firewall product which runs along side it and it has a lot more features than XP or XPSP2. Worth a look. All our W2K & W2K3 servers have it and run fine. There are also good features on setting auto scans and such like.