I view mature games to be something that evokes a level of thinking that a child would struggle to grasp or even come to. Shadow of the Colossus, Beyond Good and Evil, and Final Fantasy (before they went to carp) promoted thinking.
I am totally with you on that. When I first heard they were making a video game based on Dante's Inferno, I got so excited. Then I played the demo and was brought back down to earth... I think that's part of the appeal of SW:TOR for me. There are a lot of interesting ethical choices while you're out questing, and unless you're just breezing through and plan to go all light side or all dark side, you usually need to stop and think for at least a few seconds, before you make up your mind. Still, it'd be nice if they'd make some "regular" video games that made you think.
As far as stuff I should be too old for, I still love Disney movies and I watch them on occasion. Even though I haven't done it in years, I still get a kick out of doing coloring books. I'm a terrible artist of really any variety, so coloring is an easy and relaxing way to let myself feel artistic.