After further testing, the main problem in IE appears to be:
Leave the body alone for the most part. You can set font, color, background, margin, and padding for it. For anything else, such as the width, and to center content, use a container division (styles shown inline simply for simplicity's sake - normally they should go in the stylesheet):
HTML Code:
<body style="margin:0;padding:0;background-color:orange;color:black;">
<div style="width:980px;margin:0 auto;">
The rest of your tags and content here
</div>
</body>
I added the container division to a local copy of your page and set the body:
HTML Code:
<body style="width:auto;margin:0; padding:0;">
<div style="width:980px;margin:0 auto;">
That's my container under it. I closed my container just before the closing </body> tag at the end of the page. Took care of things here. If you remove the width from the body selector in the stylesheet and zero out the padding and margin there, you need not style the tag, similarly the style for the overall containing div tag can go in the stylesheet, give it a unique id, as there should be only the one div styled that way on the page.
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