<div class="panelcollapsed"><h2>I'm a header, yo</h2>
<div class="panelcontent" id="wanda">The stuff here.
</div></div>
<style type="text/css">
#wanda { height: 400px; overflow: auto; }
</style>
This utilizes the built-in panel collapse thing, and you just style it using #wanda for the content *shrug* for a different header, just make a .wanda-header class in the style sheet and tack class="wanda-header" on the h2.
Not an optimal solution but the easiest for you ;) If you'd rather I make you a fancy code *shrug* I can do that but.