D.S.
We traveled with our boy when he was 10 months, but it was only a cross-country trip. Still, we packed lots of books to look at, especially his favorites. We found some great books that had buttons to push and the noises went along with the story (nothing too loud that would annoy other passengers) and he loved those.
Toys are great, but nothing with too many pieces that might get lost on the plane. MagnaDoodle was a fun toy and because the pen was attached, it wouldn't get lost like crayons would. Stuff that has buttons to push or light up are great at this age. Our best toy was a light up spinny wand that created different patterns with the light. Got it for $1 at Target and he would watch the patterns for minutes on end. Another was a toy remote control with Sesame Street characters on it. Wrap any new toys like a gift so he can have the fun of unwrapping them.
We also took a travel DVD player and a couple of movies. If you're going to do that though, I'd suggest getting him used to headphones now. My son didn't like the small headphones that rested on his ears, he preferred the large noise-cancelling ones that covered his ears completely.
Out of desperation, we made toys out of things that were on the plane. Airsick bags make great hand puppets and it was fun to look through the magazines for things he could name (dog, baby, etc.). For some reason, tearing apart a paper napkin and throwing it like confetti was hilarious. He also loved to just look out the window and watch the world go by.
And for popping the ears, just make sure he's drinking something at takeoff and landing. That usually takes care of air pressure problems.
Good luck!
D.