I'll add something here I guess. (second post)
Having SpybotS&D with it's resident blocker loaded, and immunization updated you'll almost never have to worry about spyware, or adware again. Spyblaster is overkill, but if you don't mind using more resources, go for it.
Adaware has gotten redundant, as the free version does less than SpybotS&D, is very clunky when scanning, and has no way to block unwanted progs from being downloaded.
For pop-up blocking, I recommend the Google toolbar, I know Google is kind of questionable on some policies, but I use it for searching as well as pop-up blocking. It's not %100, so I also use the built in pop-up blocking packaged with the newest MSIE, installed with Service Pack2.
The end-all option is to use FireFox, but using opensource programs is for very advanced users that have the time to mess with program settings that average users have no idea even exist. Along with really no technical support, other than other users (who tend to run on the stuck up side).
Hope this helps some.