TMNT Turtles in Time on SNES. Its a fun game and kids can button mash, and turtles are still relevant today. Puzzle games like tetris can be good for using the brain. There were a ton of puzzle games in the snes era, like bust a move (puzzle bobble), yoshi's cookie, puyo puyo (kirby's avalanche), and many more.

I would mostly avoid NES because it looks really dated, aside from a handful of the real classics like Super Mario Bros 1 & 3.