Why does IE6 Double My Margins?
If you compare your site in multiple browsers and find that the margins are twice as big in IE6, you've run into a big called the double margin IE6 issue. A known issue, it happens when you style a margin onto a floated element. Luckily it's an easy fix: add the style attribute “display:inline” to the column with margin.
Then your IE6 version should obey your stylistic vision. Unless of course you have more style problems, but at least this won't be one of them...