Esto es algo que arma automaticamente el DWeaver...
Espero que te sirva...
Código HTML:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>Documento sin título</title>
<script type="text/JavaScript">
<!--
function MM_jumpMenu(targ,selObj,restore){ //v3.0
eval(targ+".location='"+selObj.options[selObj.selectedIndex].value+"'");
if (restore) selObj.selectedIndex=0;
}
function MM_findObj(n, d) { //v4.01
var p,i,x; if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
if(!(x=d[n])&&d.all) x=d.all[n]; for (i=0;!x&&i<d.forms.length;i++) x=d.forms[i][n];
for(i=0;!x&&d.layers&&i<d.layers.length;i++) x=MM_findObj(n,d.layers[i].document);
if(!x && d.getElementById) x=d.getElementById(n); return x;
}
function MM_jumpMenuGo(selName,targ,restore){ //v3.0
var selObj = MM_findObj(selName); if (selObj) MM_jumpMenu(targ,selObj,restore);
}
//-->
</script>
</head>
<body>
<form name="form1" id="form1">
<select name="menu1" onchange="MM_jumpMenu('parent',this,0)">
<option value="http://www.gmail.com">gmail</option>
<option value="http://www.forosdelweb.com">FDW</option>
</select>
<input type="button" name="Button1" value="Ir" onclick="MM_jumpMenuGo('menu1','parent',0)" />
</form>
</body>
</html>