In my day, I spent hundreds of hours playing Quake (and I don't think I've seen anything that matched it), but I no longer have the time, energy, patience, or remaining carpal tunnel capacity to put up with learning some game's 17 inverse lower Egyptian Ninja super power spin moves. Plus, I have little kids and a wife, so unfortunately the spurting gore- and slut-fests are out.
When I get home from a long day at work, I want to blow up easy-to-hit baddies for a while, or walk around in an interesting and well-written environment. I don't want to see "game over" or even be sent back to the "beginning of the level". Better yet, the game should come with a "god mode" accessible from the very beginning--I bought the damn thing, I'll decide how much I'd like to "cheat".
I'm having trouble finding good games like this, but I have plenty of money burning a hole in my pocket if someone can point them out to me. Zelda Wind Waker was not too bad, though really too difficult to be really entertaining. At this point, Lego Star Wars is about as good as I've found.
That's what "casual" is to me. I have a Wii. Game suggestions welcome.