try this.. :)
<html>
<head>
<title>Nirav Demo</title>
</head>
<body>
<div id="DivHeader" class="Header">
Header File With Menu.. :)
</div>
<div id="DivBody" class="Body">
<iframe id="MainFrame" style="border:none;height:500px;width:100%" src="index.html">
</iframe>
</div>
<div id="DivFooter" class="Footer">
Footer
</div>
</body>
</html>
you can change iframe source dynamically using javascript ..so your header and footer will remain same on all pages and your body part can be vary according to your need.. :)