Beginner question - On Enter Video?

Hello!
First of all, sorry for bad english / any grammar errors, I'm still learning =)

Recently, I've read a few pages in XBMC Wiki, on how to develop a skin.
Instead of creating a new one, as a matter of self-teaching, I am playing around with Confluence, making a few modifications and see how it affect the skin. Up to now, I've done great progress, the Wiki pages are clear and easy to understand, I could achieve almost everything I tried, mostly in MyVideosNav file.

Except for one thing.
See this image bellow:



This is my Videos Library screen. When I press [ENTER], XBMC will start to play the selected video.
All I want to do, is run a script, using XBMC.RunScript(), whenever I press [ENTER], just before the video start. But I couldn't figure out how to do that, couldn't find any events triggered.
Is there an <onclick> tag, or anything like that for that particular task?

Thanks in advice!