After initializing my main HD and reinstalling everything (I was having trouble with an audio recording app), I suddenly developed an intermittent "screen freeze" no matter what I was doing on the computer. I ran SpyBot and Fix-It Utlities 6, but couldn't find any problems, adware, viruses, etc. The computer is used for internet e-mail and audio, and a little browsing, but that's it.

I rad AdAware after a suggestion from Geeks to Go, and found this:

ALEXA
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obj[27]=Regkey : software\microsoft\internet explorer\extensions\{c95fe080-8f5d-11d2-a20b-00aa003c157a}
obj[28]=RegValue : software\microsoft\internet explorer\extensions\{c95fe080-8f5d-11d2-a20b-00aa003c157a} "MenuStatusBar"
obj[29]=RegValue : software\microsoft\internet explorer\extensions\{c95fe080-8f5d-11d2-a20b-00aa003c157a} "Script"
obj[30]=RegValue : software\microsoft\internet explorer\extensions\{c95fe080-8f5d-11d2-a20b-00aa003c157a} "clsid"
obj[31]=RegValue : software\microsoft\internet explorer\extensions\{c95fe080-8f5d-11d2-a20b-00aa003c157a} "Icon"
obj[32]=RegValue : software\microsoft\internet explorer\extensions\{c95fe080-8f5d-11d2-a20b-00aa003c157a} "HotIcon"
obj[33]=RegValue : software\microsoft\internet explorer\extensions\{c95fe080-8f5d-11d2-a20b-00aa003c157a} "ButtonText"
obj[34]=RegValue : .DEFAULT\software\microsoft\internet explorer\extensions\cmdmapping "{c95fe080-8f5d-11d2-a20b-00aa003c157a}"
obj[35]=RegValue : S-1-5-18\software\microsoft\internet explorer\extensions\cmdmapping "{c95fe080-8f5d-11d2-a20b-00aa003c157a}"
obj[36]=RegValue : S-1-5-21-1417001333-1454471165-839522115-1004\software\microsoft\internet explorer\extensions\cmdmapping "{c95fe080-8f5d-11d2-a20b-00aa003c157a}"

After removing ALexa, my problem seems to have ceased for now.