Its not the webform that displays the toolbar, its how you open the webform in the browser. Take a look at the jscript for the open function of the window object. basically you will do some like the following:
<script LANGUAGE="JavaScript">
var url = "mypage.aspx"; // your url to the webform
var name = "popup"; // any name for the window, if you want to reuse the window
var settings = "menubar=no,status=no,resizeable=no,toolbar=no,scrollbars=no"
window.open(url, name, settings);
</script>
Hope this helps.