Karateka was a very old classic game. Anyway, I played it as well but I find it not entertaining enough because its quite hard to control the character.
If it is street games, the first game that I played is hide and seek, and if it is online games, the first game that I played is the street fighter.
Haha, thumbs up fror this thread. Guess mine first gaming experience is related to Tetris and Pacman. Yet, the best old-school game is surely Mario))