Jack Thompson is the guy who raised ruckus about games like Grand Theft Auto and several others. On September 25, 2008, Thompson was officially disbarred by the Florida Supreme Court, effective October 25th, 2008. Kotaku Thompson's response
You don't, nor will you ever need a toolbar. They're useless add-ons that integrate into the Explorer shell and can cause a number of issues. To reset your user agent you can either use SUPERAntiSpyware or use this registry file for IE7 on XP. Avast (do a minimal install) is the top pick for an AV for me, Avira's AntiVir is also quite nice.
I'd remove any/all toolbars, uninstall AVG and Spyware Doctor. Spyware Doctor is useless, AVG has lost it's quality, and toolbars can really mess with Windows Explorer, etc.
I recommend the Professional package choice in my Anti-Malware Toolkit. I've been getting very fond of SUPERAntiSpyware lately too. It works quite well, though all of the tools are essential in their own way.