Please Help! Google searches won't load =(

Well my computer was recently bombarded with viruses but after running MANY tests from Spyware Doctor, Avast, Spybot: Search and Destroy, and Verizon Internet Security, Verizon and Spybot always came up blank or the promblem still continued after a scan so i uninstalled them. I installed Avast and Spyware Doctor and after running a scan with Avast the problem seams to have been solved. But now Google, Yahoo, and alot of other search engines do not load when i search somthing. Some pages wont load either (just the ads load) The progres bar is completely blank. I use the browser Mozilla Firefox but i dont think internet explorer works either. Also, pages seem to take longer to load aswell. Could it be that 1 of my antiviruses did somthing? Could i still have a virus in my system? Whenever i run a new test it always shows viruses yet the last scans always claim they found and deleted all viruses already. i dont think firewalls are the promblem either.. also, i tried system restoring but i didnt hav a restore point going far enough to fix this but ill try again... plz help me. p.s would reinstalling firefox or another new browser help?