I'm definitely not an expert... just have picked up the jargon (and probably miss-used it actually.)
Anyway, here's what I'm thinking. I've reviewed a lot of source code in developing my first site and, like I said, have never seen so much positioning code. (That's the stuff in your HTML code which defines all those pixels and absolute positions, etc.) Did you manually program all that or use some type of editor (like FrontPage, Homesite, Dreamweaver, etc.) I would guess you used an editor. If so, it would appear to me that you have some option selected which is causing the program to insert all that code. That is where I suspect the problem to be.
What I mean by dynamically rendering is to lay out your page in relative terms (images are centered in a table, for instance, and not 600 pixels from the top). That way, the browser just pretty much makes everything fit and doesn't get stuck into shoving things into particular spots. Getting a page to render is more of a suggestion than a command. I believe that designing for maximum flexibility is the key.
Go look at my page as an example and view source code. Then compare that to your source code and the difference will be obvious.