I would use a layout something like this:
I have left out the header and footer divs as they are independent of the left, central and right divs
PHP Code:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title></title>
<style type="text/css">
<!--
#content {
width: 100%}
#left {
width: 100%;
background-color: orange;
overflow: hidden}
#right {
float: right;
width: 25%;
background-color: green}
#central {
float: right;
width: 50%;
background-color: blue}
-->
</style>
</head>
<body>
<div id="content">
<div id="left">
<div id="right">
Some ads<br />
Some ads<br />
Some ads<br />
Some ads<br />
Some ads<br />
Some ads<br />
</div>
<div id="central">
your content<br />
your content<br />
your content<br />
your content<br />
your content<br />
your content<br />
your content<br />
your content<br />
</div>
<ul>
<li>Menu item 1</li>
<li>Menu item 2</li>
<li>Menu item 3</li>
<li>Menu item 4</li>
</ul>
</div>
</div>
</body>
</html>
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