So, a lot has changed since I originally made my poll asking which version of D&D I should start with. Settle in... this is gonna be a long one.
My first rules set that was not just a Fast Play game was the Pathfinder Beginner Box, and me and my friends had some great times with it. The physical quality of that set is excellent, and I've been using the Flip-Mat that came with it for most of my subsequent games.
After graduating from high school, we didn't play much due to one of the players moving to another city. I took a hiatus from running games (as instigator, I almost always have to be the DM), except for a brief ill-fated session with the Beginner Box again. I also didn't play much, since no one ran very many things at my university... or so I thought.
Fast forward several years, and I get invited to two separate games. One is a Savage Worlds game run by one of my friends in graduate school (which alternated with his friend's D&D 5th Edition game, thereby introducing me to those rules as well, and the other is a rotating group of GMs in various systems. My first session with this crowd was a Star Wars Saga Edition game, in which I was immediately impressed by the skill of the GM; though he has moved and I don't talk to him as much now, he remains probably the best GM that I have ever played with.
During this time, I've been running D&D only occasionally. My game of choice initially is the Basic Rulebook from 1981, edited by Tom Moldvay (which, together with Dave Cook & Steve Marsh's Expert Rulebook, makes up the "B/X" system). It goes pretty well, but it soon appears that my players want more options, and I want them to have a few more hit points, so that I might challenge them more. Since I already have the books, and the characters can be converted with little trouble, I choose Advanced D&D, 2nd Edition. I've stuck with it ever since, due to the ability to run the game smoothly without using any of the fiddly optional rules like individual initiative or spell components. Unfortunately, I missed out on the premium reprint... that's what I get for dragging my feet.
Aside from 2e, I've experienced a number of systems from both sides of the screen, and read through several more without getting to run them. I've quickly discovered that "old-school" versions of D&D (and the related retro-clones) are much more appealing to me. Partly this is due to the rules bloat of later iterations of the game, exemplified in Pathfinder, which I have sworn off completely due to the length of character creation and the attendant reluctance to kill off PCs if the dice fall that way; D&D 5th Edition is not as bad, but I still don't see myself ever running it due to numerous things about my campaign setting that wouldn't work in 5e - not the least of which is the vastly differing level of magic present in each.
On this topic, for anyone interested: What are some specific things that you enjoy about your favorite version of D&D or a derived game? (Obviously I don't want to start an edition war, so hopefully this can be kept positive - why you love "X", as opposed to why you hate "Y".)