When my peers tell me they don't like Atari games I think it's cause they never tried it. i fail to see how anyone could have played one of the better games and not like it.
It's probably a graphics issue. People who grew up with the NES often scoff at the Atari 2600 because the graphics look primitive compared to their favorite retro system, but you don't need great graphics for a game to be fun. Try starting them in with Pitfall II, H.E.R.O., and Kung-Fu Master.