My favorites from a mechanical standpoint are typically 3rd person shooters or action games. Games with perspective like the Arkham Games or the Resident Evil remakes.
As for genre, that's a tough call. It's easier to say what I don't like. I don't typically like jrpgs or anything with an anine art esthetics, although there's a lot of exceptions.
I also like old-style 2D Zelda games and those like them. Also twin stick shooters.
As for the settings, I like a good horror over pretty much anything else.
I like my games to have a story. I can enjoy any game mechanic if the story is good enough.