I have made a simple page for a sound board that I made. I use Chrome actively and it looks how I would like it. I’ve tested it in Safari, Firefox, and, Chrome. Here is a picture of the site, at http://nkonecny.com/monkeyislandsb:

As you can see in IE9 the margin is completely wrong, there is a broken image looking box at the top right, and towards the bottom the second Ad and footer are gone. I would post code but I slightest clue of where the problem lies so I thought it would be easier to direct to my site and view the source. Please let me know if this needs more clarification.
Remove the HTML comment from before the DOCTYPE. Putting anything before the DOCTYPE triggers Quirks Mode in IE.
Also, that broken image thing is coming from your
<img>tag, whatever that’s there for…