For me it was definetly the 1.4.2 - 1.5 era i was mostly playing survival and sometimes multiplayer,everything was much simpler back then and this versions were the best suited for solo survival experience i would say.Although my first playgthroughs were on creative after i bought the game that was in version 1.2.4 when i learned the basics still with the old creative menu which is nostalgic in my opinions :D.
Last good times in minecraft for me were 1.7.4 Guild and Factions server.Right after this i took a break and minecraft never became my main game after that.
Welll, I started playing Minecraft in early 2017 in Minecraft pe, so my favorite version would be 1.2 (or 1.12 of java) because update aquatic started like new minecraft and I dont like that. I know i am not a veteran but at least its not new minecraft
I was incredibly young at the time but I remember playing minecraft pocket edition. I think it had just come out at the time. I definitely remember the nether core and using it for decoration in creative though. And when the nether finally came to the original pocket edition, I remember being enamored and terrified with it. I can’t remember the exact versions those were but that and legacy console edition, before the aquatic update made up a good portion of my minecraft experience in my childhood.