The game you described sounds like Qix You got to kill the spiraling thing in the middle of the screen, or get over 50 % of the screen cleared. It was a great game back then. Sure was hard though.

Yeah, 2600 version of Moon patroll used up to jump, and fire to shoot. The 5200 has two buttons though, so they use one button to shoot, and the other to jump. It was a lot easier.