might be some weird setting on your video card resolution. go to the control panel, display...and mess around with it a bit. just make sure you remember the settings they are at...do this last before the steps below though...
try clearing your cookies and everything first....run anti-spyware and anti-virus too, could be that. also check if your anti-virus is blocking things..sometimes some block scripts....there is an option as well to not display images within the web browser i believe...in firefox, its in the content option in preferences, "automatically load images". some anti-virus if you install it will do these automatically.