I believe my computer has a virus… please help?

Ok, for starters, I’m not stupid when it comes to computers. But I’m having some trouble now that I can’t seem to find a cure for. Ok well the other day I downloaded what I thought was a clean program, but it wasn’t and upon downloading I immediately got a warning from my virus scan software (mcafee I believe), anywho, I clicked ok on it but that doesn’t take care of my problem… here’s what my computer is doing… it works fine except it won’t load certain websites. Such as myspace, yahoo (I’m on the laptop now), google searches, and other things of that nature… but it’ll load certain other sites such as ask.com and paypal.com… What is the cause of this? I have ran both ad-aware and mcafee scans with no luck… I still can’t get it working… and also I realized if I open a proxy and then try to go to myspace, it works… so whatever this “worm” is, is blocking me from certain sites… how do I get rid of it? I can’t seem to do so with the scans I am running now.

scan here.

if something comes up, its virus or malware. if not, the issue is related to something else on the machine.

http://www.eset.com/onlinescan/
http://www.kaspersky.com/virusscanner

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