What is the best freeware is a matter of taste and opinion though many will agree with me on these:
Mozilla Firefox with NoScript, PhProxy-InBasic, McAfee SiteAdvisor, Image Zoom, IE Tab, Firebug, DownloadHelper, CustomizeGoogle, Adblock Plus, Adblock Filter.G Updater, Adblock Element Hiding Helper, RefControl (set to block referrers) , CS Lite, Refcontrol. This is just simply the best set up!
Online Armor Personal Firewall darn good for a free firewall
Avast! Home Edition paid antiviruses are better but this is sufficient
PeerGuardian IP blocker but