Hope this will assist you.
(1) The 'width' and 'height' params is the size of the popup window the user will first see when active.
(2) The 'resizable' param allows the user to resize the popup window to the size they want.
I used javascripting:
<script language="JavaScript">
<!--
function popup(){
cuteLittleWindow = window.open("real1.html", "littleWindow", "location=no,width=485,height=200,
resizable=yes"

;
}
//-->
</script>
Within your HTML to call the pop window :
<table align="center" border="0">
<tr>
<td align="center"><FONT SIZE=-1 color="white" face='Verdana,Helvetica, Arial, MS Sans Serif'>Click<p>
[<a HREF="javascript

opup()"><b>Label </b> </A>]
</td></font></P>
<td></td>
</table>
Good luck.