Tobias Andersen made a great list at letterboxd.com/tobiasandersen2/list/random-movie-roulette/ and I've watched some great (and not so great but bearable) movies because of it. However, as I'm weirdly picky at the moment, and because his list legitimately had hundreds of movies I'd already seen, I decided to make a list of movies from 2005-2020 that I want to see. This will definitely change constantly but hey. There are all sorts of genres too, since I can watch almost anything.
If you're interested in trying it yourself, grab a number range at random.org and it will give you a truly random number. That's if you wanna play along at home.