I was introduced to RPGs in 1981 with the D&D Basic set edited by Tom Moldvay and the Expert set edited by David Cook with Steve Marsh. I was only eight at the time, but my father let me play anyway, and my older brother was the DM. Before that I had been familiar with hex based war games from Avalon Hill and Gideon Games
I grew up with the hoby from that point, dabbling in Advanced D&D for a while, until the second edition, and I couldn't really find players for a while.
I played the old d6 Star Wars, Time Lords d20 and Tales From The Floating Vagabond in the 90s, also dabbling in Call of Cthulhu and Vampire The Masquerade.
The difficulty in finding players and groups eventually lead me to computerized gaming, and Neverwinter Knights. I got into world creation at that time, and began constructing adventures. My cousin had a persistent world, which he shared with me, but wanted to make it a new setting rather than using published setting material. After his death, I continued the work of turning what we worked on into a setting of its own as a tribute to him.
For two years I was a founding member of a gaming group that took turns GMing. We played mostly D&D 3.5 but I also gave my hand at white box D&D using Keep on the Borderlands - the module I had began with back in 81. My next turn DMing, I thought I would give the group a taste of the world my cousin had started, and I was continuing to work on. The series of adventures that these players experienced coalesced into yet more setting material, as did a cosmology that an other friend developed and allowed me use of.
My attempt at 4th edition D&D just did not go that well. The feel was too high powered for my tastes, so I ended up going even more into grognardia than 3 .5 had lead me.
Other games I have checked out are Talislantaa(each edition), Labyrinth Lords, Basic Roll Playing, Kobolds Ate My Baby, and MERP.