Instead of a dvd why not a cassette player? You can get some great books on tape from the library, when dd's were little dh and I would read some fav stories on tape for them, works great with or without the corresponding book.
Color wonder is great, I saw a travel size pad with a hard back - great for the airplane. Also model magic if you think the baby/toddler won't mouth it. Like playdough but not messy and best of all NO ODOR.
Stickers and plain paper, a new coloring book as well as just a roll of tape would keep my girls busy forever.
I also got some lolly pops and fruit chews. They have arthur, disney, dora and many others now. My girls never got these at home so on the plane they were new and helped with the ear pressure. Avoid milk - they won't make the toddler sick but if they do happen to be airsick - you won't want them to have had dairy!!
If your flying duirng meal time pack something appropriate to tide everyone over as most airlines won't serve food esp on a 2 hour flight.
A sports bottle or sippie cup with water or clear liquid also helps with ears and hydration. Most people don't realize but we all are prone to dehydration when flying.
Have fun and relax
TJ