<script Language="JavaScript">
<!--
function popup(url, name, width, height)
{
settings=
"toolbar=no,location=no,directories=no,"+
"status=no,menubar=no,scrollbars=yes,"+
"resizable=yes,width="+width+",height="+height ;
MyNewWindow=window.open(url,name,settings);
}
//-->
</script>
<?php
bla bla
<a href=\"#\" onClick=\"popup('http://www.blabla.com/index.php', 'Win1', 200, 300); return false\">Collegamento</a>
?>
-------------------------------------------------------