Pop up window on button click

go this link

       
        Hi munesh

                I have already tried this. but this opens new window not a pop up window.
                i need a pop up window on button click.in which user can enter data.
       
        thanks

Go to this link

And without this

type="text/javascript">

function openContactForm()
{

var win = window.open('contactus.aspx','Contact Us','width=200,height=100');

}



href="#" id="contactLink" onclick="open_contactForm()">Contact Us