This is purely a javascript thing. You just print your javascript source in <script language='javascript'> code </script> tags and the browser takes care of the rest, the server and perl have no ability to affect how the browser handles the javascript code. In your particular instance, the target anchor would do nothing, since the link would have to be clicked on to open the other window, and you don't have any link text. The javascript you have would also do nothing, since you declared the open_window function, but never executed it. Check your javascript references again and try writing your javascript code in a static html page and get that working first.
-Syn0