Splinter Cell chaos theory is by far the best shooter in terms of single player and co-op. It doesn't require good aiming but relies heavily on strategics and stealth. The 2 player co-op is absolutely fantastic it relies heavily on teamwork and communication and is very satisfying. And the lightning effects are so good that this 9 year old game doesn't fall behind current games far in terms of graphics.
Starbow, Many of us have missed your SC1 succes so it would be nice to see you play this arcade game that is a combo of the sc2 gaphics and the sc1 units and mechanics.
Another absolute classic any of the Commandos games a WW2 game in which you control a small team of commandos (all with unique abilities) to sneak around and take objectives. It is a top down game containing some awesome rare mechanics like the option to create multiple view-ports to track different units/places of the map.
And a recent game: Hotline Miami is totally fun to do. But it is a bit violent.