widgetizing the sidebar issue

hey guys I want my widgets to have this code

<li class="widget">
<img src="<?php bloginfo('stylesheet_directory'); ?>/images/widget-left.jpg" alt="widget-left" />	<h2 class="widget-title">Categories</h2> <img src="<?php bloginfo('stylesheet_directory'); ?>/images/right-widget.jpg" alt="right-widget" />
<ul>
<li><a href="#">Category1</a></li>						<li><a href="#">Category2</a></li>
<li><a href="#">Category3</a></li>
<li><a href="#">Category4</a></li>
</ul>
</li>

In my widget-title section I have used two images

I want to know how you will specify the thing in the function.php

<?php 

if ( function_exists('register_sidebar') )
    register_sidebar(array(
        'before_widget' => '<li class="widget">',
        'after_widget' => '</li>',
        'before_title' => '<img src="images/image1" />><h2 class="widget-title"><img src="images/image2" /> ',
        'after_title' => '</h2>',
    ));
?>

this code won’t satisfy pull in my images and what should I do