Hmm what resolution did you design the site on? You do realize not everyone has the same resolution as you. I have about 300px of horizontal scroll in FF and IE. I'm on a 1024x768 res. In IE for PC there is an image in the top right corner that doesn't seem to match the colors of the rest of the site. Try www.browsershots.org it takes a few days for results but its free. www.browsercam.com isn't free but the results are almost instant. Your CSS is invalid.
should have a ; after right but if you add it, that breaks your layout. Try this for the relevant CSS
That gets rid of the horizontal scrollbar in IE and FF. It was that 500px right padding you had causing the problem. You also don't need values on 0 units in CSS unless its line-height.
font-family: Arial, Geneva, Verdana, sans-serif;
background: #FBF2E3 url(images/home/lines.png) repeat-x;