Thiese changes needed a change in the source code.

You can look in the theme.css file for whatever theme you are using..  In that file you can change the "padding" of the cells, and that should take a lot of the extra space away. Look for things like:

padding-left: 5px;
 padding-right: 0px;
 padding-top: 4px;
 padding-bottom: 4px; 

and things like:

TD.Gallery_FileML {
 background: url('Images/frame_middle_left.gif') repeat-y top right;
 padding: 0; 
}