My first actual game was Donkey Kong II handheld. Got it in Hong Kong when I was 14. Used to clock it 3 times on one life until it got so damn fast....
That was the only game I had until I was 17 as we weren't allowed any game systems.
Once I was living on my own @ 18 boy did my Mega drive and the local video shop arcade machines cop a flogging.
Most early Sega addictive game was Final Fantasy VII. Played it so much for so long I started dreaming about it every night so I had to have a break for a day.....damn gaming addiction.