I've been using AVG for about a year now and have had no problems with it. It updates automatically, can run scheduled scans, and handles emails with no trouble. I keep the Windows Firewall turned on, but I also use the Spybot S&D Resident/ Tea Timer, which can protect your registry from unwanted changes. I seldom have the need to access risky sites, but the couple of times I have the AVG has stopped any attacks.