Need to run a basic javascript stopwatch within a wordpress site, that has the ability to submit the time elapsed via email.

So someone clicks start, and then when they are finished watching, they click stop and then enter their email and submit it, to a database or just send an email.

I could use a form builder plugin, however I am not sure of the best way to integrate the script into the form. I am not real experience with java. So any help would be greatly appreciated and please give as much detail as possible.