I spend a lot of time working on computers and testing software. For the past 2 or 3 years Ive been recomending pctools spyware doctor. Well my pimping of that product has ended. It doesnt work as well as some of the competition and its become a somewhat bloated resource hog.
Currently Im recomending Zone Alarm anti-spyware. Its been doing a great job on the few pc's ive tested it on and the impact on resources is low. Its priced very good too.
Check out the 15 day trial if your having issues.
http://www.zonealarm.com/store/content/catalog/products/sku_list_zaas.jsp?dc=12bms&ctry=US&lang=en&lid=trial_zaFamily