I have one with urbz, nintendogs, tetris and so on (quite grown up games but then it is mine lol!) and ds who is nearly four can play a bit on nintendogs, stroking them, walking them, feeding them etc but he doesn't get the concept of the tournaments etc although if I'm honest I'm not great at it either!
We're going on holiday in June when he'll be 4 years and two months, and I was thinking of getting him a game for his birthday so he can also play it on the plane - has anyone got any suggestions for something he'll be able to play?