Код:
<html>
<head>
<script language="javascript">
<!--
function loadPage(){
document.all.y.src="a.html";
};
-->
</script>
</head>
<body>
<table width="500" height="100">
<tr>
<td width="100%" bgcolor="#FF0033" onClick="loadPage()"></td>
<td><iframe name="y"></iframe></td>
</tr>
</table>
</body>
</html>