I've got a couple pages with this kind of thing, and I have only been able to debug some of them. In every case where I did find a fix, it required eliminating all extra spaces and hard returns in the code. The code you posted here has a few extra spaces between tags -- that's where I'd start.
Also, just for good measure, there are some tag nesting errors and unclosed font tags/center tags -- they shouldn't be a problem, but getting rid of them sometimes helps.
Yeah, extra spaces and returns aren't "supposed" to matter in HTML -- but tell that to the browser makers!