Hi K.,
My 2 year old started his travels with Seattle at 10 wks, Tennessee at 6 mos. He's now 2 yrs old has been on an airplane 3 more times including Cancun at 22 mos. The key to all our travels is look up a supermarket/Target/Walmart address in advance and stock up after we get to our destination. Just packing diapers for 5 days can take up half a suitcase.
We also ask for a room with "honor bar" refrigerator or request a rental mini frig when making our reservations. I'm sure you're aware that hotels also have cribs by request but do it early since inventory is low.
Another step that has helped the air travel go by more smoothly is taking a couple new books or toys. (Mini board books or, now that my son's older, paperback books are easy to throw in a carry on bag.) The "newness" of a toy always seems to hold our little guy's attention longer.
Remember to always have your son drink something during take off and landing to help aid ear pressure but don't be surprised if he gets an earache. Your pediatrician will tell you that is common with air travel.
Now that our son is older we have him help us plan the "airplane picnic". Since we have found that morning flights are the easiest for him, we pack bagels, raisins, cheese slices, apple slices, etc and have a healthy meal or snack without having to rely on the airlines anymore. By the way, on my last trip home from Florida, only one drink service was offered and NO snack.
Lastly, I promise, we now take our travel DVD player on every trip. It definitely helps to have Pooh or Wiggles get him through an hour of travel. It's so hard when they're toddlers to make them understand that they have to wear a seatbelt for 2-3 hours and be polite the entire time.
Have a great trip & good luck!