Hm, this is a tough one. The Princess Bride is definitely up there as I watched that a bunch as a kid, along with Toy Story and the Aristocats (all on one VHS). Nausicaa and the first Star Wars are definitely up there too.

In my adulthood the Toy Story and the Aristocats are the only two I haven't rewatched consistently (though I'd like to with the latter!). There's still a lot of Princess Bride & Nausicaa, I watch through all the Star Wars' a couple times a year, but my adulthood comfort movie has been Baby Driver.

It just seems to check all the boxes for what I need. It's not too slow, there are a bunch of subtle details, it's fun, it has good heart and emotional connection to the characters. It has a lot of homage, particularly to the movie Drive (2011) while managing to stay a completely separate film. I can't say how many times I've watched it, it at least as many times as the others, just in a shorter period of time.

The only issue with the movie is that it has some problematic actors, Kevin Spacey and the main character played by Ansel Elgort. Despite their IRL problems I don't really mind separating them from the film. And the rest of the cast is just stellar.

There are others but my Plex is acting up so I can't check my playcounts