I highly recommend Avatar. I would watch it for Uncle and Sokka alone. I like a show with good banter. The wife and I are both eagerly awaiting the new episode, which is now something like 5 weeks late.

There are several things you have to willingly suspend your disbelief on--the largest of which is the physics, and the second largest of which is the low mortality rate. You'll see what I mean on both counts as the show goes on.

And the lessons that are imparted are not always the ones that "ought to" be. The show's creators are pretty good about subverting the message from time to time.

Oh, and the behavior of the main characters makes many hundreds of percents more sense if you mentally add two to their stated ages.