go here and download there Ad-Aware program. it's free, there is a version with more bells if you pay. .
http://www.lavasoftusa.com/
also download their refupdate program too. .
it will download updates for the datebase of spyware and crap software.
Found out about Ad-adware here on TDR,,,been using it works great. They just released the update program. .
Only thing you must remember todo with the refupdate program is go to the configuration menu and point the software to the same place that Ad-Aware is pointed to for it's database file of bad programs to look for.
Popup can come from another source thats not spyware . . there's a program call BHO Cop. . it's at
http://www.zdnet.com/downloads/stories/info/0,,77432,.html
it will detect the source in your registry and allow you to get ride of it. .
Lavasoft also has a registry cleaner that can help with this problem too.
All good honest software.
Lavasoft has a good support message board too.
good luck
Bob