Question Dave, I tried using the openDNS servers but that didn't work either.
Answer If you can lay your hands on a "Live-CD", boot up your system and access then access the websites. If you are able to do so (I'm sure you will be) - it would indicate that some of your Windows system files are probably damaged / corrupt / partially working.
You could then attempt any of the options below
(a) a re-install of the Windows operating system - over the existing one
(b) Format & re-install O.S. (you would need to backup all your data)
(c) install a "virtual machine" - like Virtual Box / VMWare and install Windows within that
Options (a) and (b) would be the easiest. Option (c) would be interesting / challenging - provided you have the time / inclination for that kind of thing.
