I've yet to play D&D in real life (it is virtually unknown in my country), but I've spent years playing it online.
I play only 3.5e and Pathfinder. I tried 4e, didn't like it. I didn't try 2e, but for what I read about it, the fluff was excellent but it was quite unforgiving, so I doubt I'll give it a try. I might give 5e a read, but I became heavily disillusioned with it a few months ago so I have no hopes of it being good at all.
3.5e is definitely the edition for me. Pathfinder is... meh. It has some things I really dig, but for every instance of something I like, there's an instance of something I detest. So I'm very lukewarm about it.
I'm only in two campaigns right now, both solo instances with the same player (we DM one each). The one I'm DMing is a post-apocalyptic heavy-intrigue affair with murder mysteries, dark secrets and politics, and the one he's DMing is a more lighthearted, relaxed, standard game.
After being spoiled by how comfortable solo campaigns are, I doubt I'd ever play in a group again. I've yet to have a single good experience with one. I also doubt I'd ever play D&D in real life either. I don't imagine myself having any fun.