codice:
<html>
<head>
<script type="text/javascript">
var w = screen.width;
var h = screen.height;

if(w>=1680) window.location="for1280.html"
if(w>=1280) window.location="for1280.html"
if(w>=1024) window.location="for1024.html"
if(w>=800) window.location="for800.html"
window.location="forunknown.html"
</script>
</head>
<body>
</body>
</html>
HTH
Zappa