I got Space Invaders along with my 2600 in 1982 (and there was nobody at home who would really want to play Combat, the included game) so I'm guessing that I played Space Invaders first on my own personal 2600. Previously I'd played the typical games that friends would have at their house or at the store display - Space Invaders, Asteroids, Missile Command, Circus Atari, Adventure, etc.