This is totally invalid, I'm surprised any browser can make heads or tails of it (from your style.css file):

Code:
#content    
{
margin-left:-451px!important;
margin-left:0;
position: absolute;
left: 50%;
left: expression(document.documentElement.clientWidth/2-this.offsetWidth/2+'px');
}50%;
}
It should be:

Code:
#content    
{
margin-left:-451px!important;
margin-left:0;
position: absolute;
left: 50%;
left: expression(document.documentElement.clientWidth/2-this.offsetWidth/2+'px');
}
There could be other problems.