You have alot of categories, but you this could be done by modifying the categories template which right now we have two formats - a gallery layout and a forum-style layout. Using the gallery layout as a guide, you could switch to a two column format. If you know html and a little PHP, you should be able to do this yourself. http://www.michaelpierce.com/gallery/index.php
is an example of our gallery layout.
We also have customization services available if you would like to hire someone to do this customization for you.