CCK: Node Reference Theming

I am using CCK and the node_reference module. I understand how to display the node_reference link like this: <?php print $field_node_reference[0]['view'] ?>, but what if I just want the string of the URL? For instance I would like to wrap an image with the node_reference link like so: <a href="<?php print $field_node_reference['url string'] ?>"><img ...></a>. Thanks and props to who can tell me!

John