As ww said, you need to read up on JavaScript, but the basic would be to trigger an event when you check that radio button and use a JavaScript command to open a new window - assuming that's what you're after and proceed from there.

I think to achieve what you seem to be after that you're better off looking to Ajax as opposed to JavaScript because there are toolkits that I believe that will do that very quickly and then it's just a matter of gluing the code together with the requisite Perl modules. I'd suggest looking at the Dojo toolkit or script.aculo.us toolkit.

Good luck!