Ok, I posted something earlier about a background problem I was having with my website. I know now that it is some sort of transparency problem. I have a wrapper that has three layers floating above it. These three layers have transparent as the background color, even though that transparent is the default setting in CSS.
In IE, the page is decoded properly but in Firefox doesn't show the background. I have gone through my CSS and layers and everything has been re-validated. Funny thing is Firefox was decoding the page fine until last week.