Addendum: Add GMER to the list
I stumbled across the GMER rootkit detector and removal utility -- www.gmer.net -- on some forum, and I have to say it works as advertised.
I use it to list all running non/system processes, and to kill any suspicious process that I come across when battling a particularly nasty virus/spyware infestation.
GMER also also you to kill all non-essential processes while you are in normal Windows operating mode, reducing the system to a state more minimalist than Windows SAFE MODE. GMER has a command prompt box that allows you to browse to and run your desired AV/antimalware application in this minimalist mode, which is nice!
