I use PC-cillin and Spybot (decent active firewall in pc cillin stops a LOT of crap from comming in) and spybot i think is better than ad-aware.... it stops more crytical infections than ad-aware.... ad-aware i think has more focus on blocking visual-infections (more toolbars and visibly irritating stuff)
The other nice thing i LOVE about spybot is in its advanced tools (for those who actually switch to advanced mode), there is a system internal checker... which removes registry entries to missing files etc. some programs leaves a trail of destruction behind them.
Also the startup manager of spybot, tells you in detail what startup entries does WHAT, if they are needed, and if they are spyware related, virus related, or resource hogs. This is especially handy when you dealing with viruses that has names like "load power profile" or "systray" (both of which are VERY COMMON, spybot will tell you which one is the authentic one and which one is the virus).
