Stuff

<style type="text/css">
div#forum_cont {
	width:000px;
	height:000px;
	overflow:auto;
}
/* This css-code will make a box with the defined height and width, and when the content goes outside the box it will add scrollbars on the needed places. */
</style>


<div id="forum_cont">
<?php
require("your_forum_index.php_here");
?>
</div>