Just one thing I did notice while we've been traveling on a family vacation:
how your kids behave on a plane is almost secondary to how you behave on a plane w/r/t your kids. If you act like a petulant, whiny, immature brat and shriek, "Well, duh, obviously the DVD player DOES work, or how come you're WATCHING IT? Now let your sister watch Veggie Tales, or I swear, I'll--," you will engender the ill will of all the people around you.
And you won't be doing Jesus and pals any PR favors, either.