I have a much younger cousin who had this game, it’s cartoonish, but it’s actually a lot of fun, the adults ended up playing it for quite a while, so you won’t be too bored yourself.

You can play as a lot of the characters from the mario games.. like Yoshi or Bowser, and possibly other games. I think Donkey Kong was a character.

Simple controls, and it doesn’t require a lot of time either (you can basically just play right away without having to make a lot of pre-game decisions) or thought put into it (like pitching changes or whatever you might need in an MLB game). I’m not sure how complicated a game a 5 year old can play, as I don’t have kids, but this is about as simple as it can get other then the baseball game that comes w/ wii sports but that’s not really a full game.

http://en.wikipedia.org/wiki/Mario_Super_Sluggers

Was nominated for a Kid’s choice award if that means anything. Also it’s a couple years old so it should be pretty cheap, which is always nice.