If you have an iPod 4 or better, you could always get the greatest game of all time's remake.
TWEWY Solo Remix.
Also available on the iPad 2 or better.
I also think that ''Crash Nitro Kart'' is a brilliant racing game for the little kids out there. I'm a huge fan of Crash and I always was since I was a little kid. So kiddies, download Crash Nitro Kart NOW!. Or you aint gonna get any cookies :P
But Crash isn't an FPS. Why on earth would you recommend that to kids?
As for RPG's, Chrono Trigger is also available, I think.
3DS FC: 1478-4144-3572
Trying to motivate myself to play: Ace Attorney 5, Strange Journey, Skyrim.