I use Ad-Aware SE and Windows Defender. In my opinion thats a very good combination, as Windows Defender does realtime scanning, and Ad-Aware SE picks up the things things that Windows Defender didn't
Just download hitman pro, it downloads and setsup all the programs needed to remove malware; like Spybot SD, Ad-aware, spysweeper and others, it's freeware: U can download and view reviews here : http://www.techspot.com/downloads/1278-hitman-pro.html
Zone alarm, its made by zone labs i think, ive got it and its perfect, go to www.download.com and search =D
I've spent over 3 years searching for something similar to what you are looking for, and nothing beats Spy Sweeper + Ad Aware. Both of those together are more than enough for your situation.