A DVD has titles on it, every title representing a standalone feature like the main movie, a trailer, making of and so on.
If your DVD has four titles, check how long they all are. The main movie or episode will be the longest one, other features will be smaller, unless you rip a series, where all titles will be around the same length then.
Do you want to combine all titles into one MP4 file for your Apple TV?
If so, what exact DVD movie or other are we talking about?
And have you checked the ADD TO QUEUE feature yet, if that is what you are after?
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