esempio
codice:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="it">
<head>
<title>link da option e radio</title>
<script type="text/JavaScript">
/*<![CDATA[*/
function vai(){
	var f=document.getElementById('modulo');
	var sel=document.getElementById('idSelect')
	var selVal=sel.options[sel.selectedIndex].value;

	var rd=f.elements['mezzo'];
	var rdVal=false;
	for(var x=0;x<rd.length;x++){
		if(rd[x].checked) rdVal=rd[x].value;
	}
	var locStr='http://www.dominio.it/'+selVal+'_'+rdVal+'.htm';
	self.location.href=locStr;
}
/*]]>*/
</script>
</head>
<body>
<form id="modulo">
<select id="idSelect">
  <option value="mi">Milano</option>
  <option value="ro">Roma</option>
  <option value="pa">Palermo</option>
</select>


<input type="radio" id="aereo" name="mezzo" value="aereo" /><label for="aereo">aereoporti</label>

<input type="radio" id="nave" name="mezzo" value="nave" /><label for="nave">porti</label>

<input type="radio" id="auto" name="mezzo" value="auto" /><label for="auto">autostrade</label>

<input type="button" value="vai" onclick="vai()" />

vai
</form>
</body>
</html>
ciao