Eher so:

HTML-Code:
<html>
<head>
<script type="text/javascript">
<!--
window.setTimeout(document.frames.unten.location.href='neueSeite.html',2000);
//-->
</script>
</head>
<frameset rows="0,*" border="0">
  <frame name="oben" src="seite.html">
  <frameset cols="100%">
    <frame name="unten"  src="html.html">
  </frameset>
</frameset>
</html>
oder:
Window.setTimeout(document.frames[1].location.href="neuesSeite.htm",2000);