Making Header Image Clickable in MT Dark

Hey,

My friend is using MT Dark and I’m trying to make her masthead a clickable link back to the main site. Can anyone tell me how to modify the php code?

div id="header" class="container_12">
<div class="grid_5 prefix_3 suffix_3">
<?php  if (is_home()) { ?>
<?php  if ($dark_headerimg) { ?>
<h1><a href="<?php echo get_settings('home'); ?>">
	<img src="<?php echo $dark_headerimg; ?>" alt="<?php bloginfo('name'); ?>" /></a></h1>
<?php } else { ?>
<h1><a href="<?php echo get_settings('home'); ?>"><?php bloginfo('name'); ?></a></h1>
<?php } } else { ?>
<?php  if ($dark_headerimg) { ?>
<h2><a href="<?php echo get_settings('home'); ?>">
	<img src="<?php echo $dark_headerimg; ?>" alt="<?php bloginfo('name'); ?>" /></a></h2>
<?php } else { ?>
<h2><a href="<?php echo get_settings('home'); ?>"><?php bloginfo('name'); ?></a></h2>
<?php } } ?>
</div>

Thanks