Angry birds. You can get a free one with a limited number of levels so you can see if your sone likes it before paying for th $2 one, quite a few games have a short free version. There are a lot of free games but they often have advertising at when the game ends that you will need to teach your son to bypass.
Some others are Rush Hour (slide various cars around to allow a red car access to move out) and Plants Vs Zombies. Lego have some kids games. I'm not sure about educational ones but while searching for games there is an educational category.
There are plenty of memory match games (matching pairs of cards) too.
Edited by Dylan's Mummy, 09 January 2013 - 07:05 AM.