My 2600 experience is the second oldest memory I can recall. That's how big an effect it had on me! I can remember literally every detail of my first time playing video games. My neighbor had the 2600 with Pac-Man and Missile Command. The fact he had Pac-Man means it must have been 1982, which means I was coming up on 5 years old.
The sound, colors, way the paddle moved... it was intense!
Same for me. I can recall everything about that moment. Where I was, who, what the game looked and sounded like...