Mrmack,
Clearly, they search for slightly different things. Both Ad-Aware and Spybot Search & Destroy can also be "tightened down" to find quite a few other things such a Internet Explorer usage "tracks" and such. But each company may decided to call something spyware, while another does not.
If you gave us the specific registry keys, we might be able to help more, but in my opinion, its not a bad idea to use them all. After a programs finds some malware, do some research on the specific registry entry or spyware file that is detected and delete it if you want, or not, but at least you're making and informed decision.
It's a personal choice that only you can make which depends on the sites you choose to visit and the programs you want to run.
Hope this helps.
Grif
XP home, AVG antivirus, Zone alarm, spyware blaster etc, third pary cookies are prompted
When I run Adaware and Spybot they report no intrusions. Pest patrol reports 3 registry keys and Spyware scan reports 20.
Why the large discrepencies?
Thanks in advance

Chowhound
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