I've done something like this before in a different theme that was... well, more simple.
My category "Articles" displayed the posts within that category on a drop–down menu.
Code:
<li class="Largenav"><h2><?php _e('Articles'); ?></h2> <ul> <?php global $post; $myposts = get_posts('numberposts=5&category=4'); foreach($myposts as $post) : ?> <li><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></li> <?php endforeach; ?> </ul></li>