Include a script follow along feature?

[StifflerStealth]

I have seen DVDs where the screen is split in three places: horizontally in the middle and then vertically from the horizontal split to the top of the screen. The video would play in the top right square, the script would be in the bottom big part, and extra info in the top left square. There would be a highlight on the corrently spoken line, but the whole script is there in the window scrolling with the speech as well.

How in the world is this done? I would like to make a custom DVD with this feature, but I don't even know where to begin. What toold do I need? Will this require true seamless branching?

Thanks,
SS