Quite simple really. I was born in 1978 so the first one out after my birth was Moonraker. That was easily one of the first ones I saw.
Star Wars had taken the world by storm the year before I was born so there was a lot of sci fi stuff around in my early years. I remember Buck Rogers in the 25th Century and Battlestar Galactica on TV and lots of space set adventure cartoon shows. Seems fitting that the first Bond film out in my existence was the space one!
What about you?