Maybe 'Chopper Command' by Activision - that was pretty good.
No Atari's here, but the v2600 was the first console I played at a friends house. Possibly playing Combat or Atlantis.
The Vic20 was the first 8bit I owned; infact I still have it, but most of the games are seriously poor compared to todays standards (obviously).
Mind you, Amok and Blitz still help pass the odd hour or two.