Your post is a bit broken up, since you have <code></code> tags inside your code. Use the alternate <c></c> code tags around sections that have </code> literally in them.

When do you expect that code to run? When the user sees the page, all the perl code has already been run. When the user clicks submit, the browser fetches a new page with the form's parameters passed to that new page. So any code you want to be run on the submit click should be placed in that other page. Or if you want to run it in the user's browser before they submit the form, then you probably want some javascript.

There should be some monks by shortly with a pile of CGI & documentation links for understanding what's really going on.