What you can do is choose a Top Menu that uses only Images (motion menus), then substitute the file used for the picture with the one you want. So, instead of a small clip of the video, you'll be able to import your button - and that's what they'll have to click on to start the episode.
My new Walker, Texas Ranger menu is like that. Instead of a image, I substituted the badge graphic. The text is non-selectable. So instead of a badge, it could be your custom button.
I know I can 'layer' things ontop of the image or button under TDA, so if instead of a badge, it was a large button background, you could lay the text ontop.