Balloon Fight is, in my view, the gold standard for pre-Super Mario Bros. games on the NES/Famicom. The physics are easy enough to grasp to have good pick-up-and-play accessibility, but have room to actually be more precise for those who want to improve. The Balloon Trip mode is a simple but fun take on the idea of an "endless scroller" kind of game. And of course, it has great music and sound effects.