Hi Kathy,
IE6 would need the content div to have a given width (percent or pixels).
If you give the content div a width of (say) 550px, float it left and adjust the padding and margin accordingly, you should be OK.
Playing with Firebug, the following changes to the style rules for the content div (at line 157 of 'screen.css') seem to be about right:
screen.css - line 157
#outerWrapper #contentWrapper #content {
background-color:#FFFFFF;
float:left;
margin-left:70px;
padding:20px 10px 10px;
width:550px;
}
