BECMI / B/X: 1985-1987ish. My kid brother and I with a few neighbor kids and a little involvement from our dad kind of fumbled around with Mentzer Basic alongside Cook Expert for a couple of years, soon adding a few modules (BSOLO and XSOLO were big for me) and a couple of 1E books like OA and Unearthed Arcana to the brew, plus some Dragon and Best of Dragon picked up in gaming and bookstores.
1E: 1988-1989, we started attending gaming conventions and playing some 1E just prior to the release of 2E.
2E: 1989-maybe 1997? I played 2nd ed off and on with friends, a couple of long campaigns and several shorter ones, interspersed with Vampire, GURPS, and getting into LARP with the Camarilla and NERO, among a couple of smaller groups. Our 2E games got increasingly house-ruled, and eventually I got away from tabletop RPG for a few years, focusing more on LARP and then miniature wargaming.
3.x: 2002ish until 2008. Ran some 3E for a few friends, and then some of my older wargaming buddies who had been into D&D when they were younger decided to start a group. This group ran steadily through 3.5 and into 4th, getting some crossover with my 90s D&D friends, before finally dissolving. We had several full campaigns run from 4th (the first one) or 1st (the rest) until the high teen levels. Two live campaigns switched from 3.0 to 3.5 mid-stream, but we started over with 4E. I also had a second group that often met at a local game store, and again ran multiple full campaigns as well as a few shorter abortive ones.
4E: Mostly from release in 2008 until a couple of years into 5E's existence; 2016, maybe? My main 3.x group dissolved, but a couple of us formed a new group with some of the 90s crew and a newer guy I met in my LARPing days. We were pretty happy with 4th in most regards, and in no hurry to transition to 5th. I also joined a 4E campaign run by my brother in 2019 and we played 1st-10th with one of my friends from the other group and a couple of brand newbies. The intent was to have a break after the conclusion of the first arc at 10th, have a hiatus, time skip and re-start the game with new adventures at Paragon, but the group wound up not resuming.
5E: My then-main group started running 5E in 2016 or so, and has played through a couple of campaigns. I played one through to 20th and then we wrapped. We had a new game meeting at a game store with a mix of three older and a couple of new players that got only a few sessions in before COVID killed it. Meanwhile I had been running a 5E game starting in Oct 2018 for a different friend group, which went on hiatus around June 2020 and may yet resume. Meanwhile one of the players from that group started running Rime of the Frostmaiden for us over Roll20 in Jan 2021, and that's going strong.
OE & OSR: I first tried out OD&D at a couple of conventions around 2010, including sessions with Frank Mentzer and Tim Kask, and this got me interested in the OSR. While none of my regular IRL gaming friends were really into older editions, I'd read forums and blogs, and usually attend a couple of conventions a year over the last decade and specifically look for old school games to play. Since the pandemic I finally embraced Roll20 and Discord, getting on a couple of servers and playing a bunch of B/X, OD&D, and running a 5 Torches Deep game since April 2020 that's still going now in 2021.