link post title to “read more” action

basically, i’d like to be able to make clicking on my title expand the post instead of taking the reader to the permalink. i’m not well-versed in PHP, but i get the sense in looking through the index template code that this would be either (a) a fairly simple thing or (b) impossible due to wordpress’s structure. does anyone know which one (if either) it is? how to do it? here’s my index template structure:

?<?php get_header(); ?>

		<div id="main">

<?php if (have_posts()) : ?>
<?php while (have_posts()) : the_post(); ?>

		<div class="entry">
			<h2 class="entrytitle"><a href="<?php the_permalink(); ?>" rel="bookmark" title="Permanent Link to <?php the_title(); ?>"><?php the_title(); ?></a></h2>

<!--
<div class="date">posted by <?php the_author_posts_link(); ?> on <?php the_time('Y.m.d'); ?>, under <?php the_category(', '); ?></div>
			<div class="dateonly"><?php the_time('d'); ?>:</div>
-->
			 <!--<div class="dateonly"><?php the_time('jS'); ?>:</div> 21th 2nd -->
		         <!-- <div class="dateonly"><?php the_time('dS'); ?>:</div> 21th 02nd -->
			<?php the_content('<p class="continue">continue reading...</p>'); ?>
			<div class="entry_footer">
<!--
{ <a href="<?php comments_link('file', display); ?>"><?php comments_number('no comment', '1 comment', '% comments'); ?></a> } :|  { Tags: <?php the_tags('', ', ', ''); ?> }!
-->
                </div>
		</div>

<?php endwhile; ?>

		<div class="prevnext"><?php next_posts_link('? prev'); ?> <?php previous_posts_link('next ?'); ?></div>

<?php else : ?>
	<h2>Not Found</h2>
	<p>Sorry, but you are looking for something that isn't here.</p>
<?php endif; ?>

		<p class="topagetop"><a href="#top"><img src="<?php bloginfo('template_url'); ?>/images/pagetop.jpg" width="80" height="20" alt="pagetop" /></a></p>
		</div><!-- /main -->

<?php get_sidebar(); ?>
<?php get_footer(); ?>

thanks so much in advance!