An emulator called, "Dolphin" allows you to emulate the Wii and Gamecube. You won't find too many roms though online, but it's useful for someone like me who owns gamecubeand Wii games but doesn't have either console anymore.
Besides that, some DX11 titles suitable for 10+ are:
Shogun 2, Dirt 2, Just Cause 2, Civilization V, Wings of Prey, etc.
All titles are 'child friendly' with Just Cause 2 being the one with the most violence but being quite fun (although the enemies bleed out and die, they do a fading injured animation.) Performs extremely well while looking good, it's also an open world game with large landscapes and terrain with vehicles.
With Shogun 2 and Civilization V, you need to worry about the processor over graphics. Shogun 2's demo is out now, hopefully the game isn't as bugged when released (Mainly shadows flickering from a normal distance.)
Wings of Prey is a flight combat simulator, quite enjoyable. It uses DX11 and Ultra settings where dx10 cards are forced to high instead. Ultimately it looks good and plays well on most cards from mid to high end.
Dirt 2 being an early (Released alongside dx11 cards) dx11 titles and AMD sponsored. It looks well, even on lowered settings. It has a combination of different vehicles, and controls well even without a wheel-pad.