Hey - we will be in WDW right after you - coming in on the 17th of October. I hope you have a great trip, here are some ideas that worked well for us, we took our daughter for the first time when she was 1.
1. If you can - rent a car. It is much easier than waiting for the buses, especially if you have a kid who has hit the wall.
2. Bring the stroller - huge help in the parks, airports etc..
3. Take it easy. Don't try to run the kids all day.
4. Do breakfast in the room. Great way to get an early start and not have to worry about the kids being hungry
5. NAPS - We would go to the park for a few hours in the morning, and bring out daughter back for a nap. I would stay with her one day, and my wife would go to the pool. The next day we would reverse - this worked very well and made for a great relaxing trip.
6. Get Groceries. In case you cant get in or have waits at the restaurant - get food you can cook quickly in your room. Having the 2 bedroom again makes this very easy for you.
Just take it slow, and go with the flow. You may not get to do everything you want, but you will be surprised at how much more enjoyable it is. Maybe DMIL will watch the kids so you guys can hit the parks one night and get in a bunch of rides!!! ENJOY