To me, the absolute minimum feature a DVD can have is the movie's trailer. In fact, if a DVD doesn't at least have a trailer, I won't buy it. I'm serious. I mean, why not? You've already got the trailer. What else are you gonna do with it? To me, if they don't have the trailer, then it shows they put no effort at all into the DVD. And I won't support people who just shovel movies onto a disc without doing any extra legwork. Now, on the other end of the spectrum, DVD commentaries are the gold standard. If there's a commentary on the DVD, I'm more likely to buy it, just to hear what the director or the actors had to say. Unless the commentary is done by, like, the key grip or the music director or someone insignificant like that.