unten mal die gröbsten fehler korrigert (habs nicht nochmal überflogen, könte auch falsch sein :))...
<html>
<head>
<title>Übersicht</title>
<link rel="stylesheet type=text/css" href="style.css">
<style type="text/css">
#topm {position:absolute;width:154px;border:1px solid #808080;visibility:hidden;background-color:#CCCCCC}
#top {BACKGROUND: #cccccc;}
#topimage {marign:0; padding:0; top:0;}
</style>
<script type="text/javascript" src="script.js"></script></head>
<body onload="INIT()" scroll="auto"><script type="text/javascript">
if(navigator.appName=='Microsoft Internet Explorer'){
document.write("Du benutzt den Internet Explorer");
}
else
{
document.write("Du benutzt einen andern Browser");
}
</script><div id="top" width="100%"><br><br><br></div>
<img src="curve.gif" id="topimage" alt=""><br>
<a href="#">test</a><br>
<a href="#" id="n">test id n</a><br>
<a href="#" id="N">test id N</a><br>
<a href="#" onClick="expandingWindow('#');return false">normal animatet open</a><DIV ID="topm">
<SCRIPT type="text/JavaScript" src="context.js"></SCRIPT>
</DIV></body></html>