There is no one program that will get them all. That's why you run more then one. Gives that one, two punch to the nasties. Now in my case I run AdAware se backed up by Spybot S&D. I keep them updated regularly and run them every day. M$ antispyware beta just don't get it for me though. It's big and clunky. I'll wait on the final release.
Something to note however for those nasties that keep comming back there is one or two things going on. One they have gotton in to the reg and when the system boots up they get activated and the ad/spy/malware program can't remove a running program. This is cured by running your ad/spy/malware tools from safe mode.
The other thing that comes to mind is like a virus the nasties have taken root in the restore points. In this case you have to shut them off and go to safe mode to run the tools.
Seti says: Turning off the restore points will delete them. But sometimes you have to do what you have to do.
EDIT: Also in Adaware you have to delete the archived items it finds. Otherwise other ad/spy/malware tools may pick up on the archive. Spybot S&D tells you about this when it loads up.
Wombat has the key as well as Seti. Spywareblaster, spybot, and MS antispyware all run in the background with no conflict or system usage. Also add winpatrol. It is a catchall for anything that tries to hijack your start menu. I have used Zonealarm free for years with no problem but that is a personal preference.