Yeah, I have the same problem you have, I can only open howstuffworks and wikipedia.
I search up in google: "water" Wikipedia's link pops up and I am unable to click it, No viruses/spyware, I've even tried Spybot search & destroy.
I've recently had an error with WinLogon.exe but I have fixed it, and now I am getting problems with Internet Explorer/Mozilla AND Google chrome.
Andrew I had a very similar problem which I solved today, it was my anti-virus programme... when I removed my anti-virus programme and replaced it with another everything went back to normal... I was running Avira free, are you using that too?