DAY 1 this is not the day you first arrive it is your first Full day.
today start out at the MK I suggest taking a Family pic in front of Main Steet with a pro. They will give you a card called a photo pass. you turn this in when your day is over and all your pro taken pics will show up on the card they can add funky little tinkerbells or other animated images to show up on the card. Just ask the pro taking the pic if you can have a mickey,tinkerbelle etc. First go straight for fantasy land for ds-3 you can have ds13 just watch on most of these rides. all of these are made specificly for toddlers. you have Dumbo, Peter Pan, Winnie the pooh, Snow White , Small World. next head for adventureland. this has Jungle cruise a boat ride with Audio animatronic animals,but a scary part that is dark for a while so just have ds3 be comforted and warned. youll see it coming. Then we have Magic Carpets of Aladin. this is like dumbo but only on carpets. so its a love it or skip it ride. Next, Pirates you shuld mabye have ds3 sit out this one. but he'll LOVE the gift shop. Then tommorow land. Do Buzz Lightyear!!this is a hit with all kids expect to do it 2 to 3 times. then we have the TTA this is a nice sothing ride on little cars up high that gently go through Space Mountain and you are able to see all of Tommorowland!!!!!! this has put many cranky toddlers to a nap. then mabye have 1 parent chill with ds3 at the hotel and have the other do the Mountains with ds13 then have everyone regroup for Wishes a nighttime spectacular at the MK
day 2
Epcot today first start out with Future World. do the land with the fam you have all these nature and health related rides and shows.this is a great educational op! then do the living seas. Big aquarium that is finding nemo thememed your kids will love this. then its the IMAGINATION pavillion yoiu can clim abord a train of thought in the sound lab and other cool stuff awaits
Then test track. this is not scary,just fast your ds3 will be fine on this if he is over 40 inches. Then have ds3 play on fountains by Test Track While ds13 does Mission Space Then the world showcase is the place to do next. World shwcase is a trip to 11 countries in 2 hours! this is the other part of Epcot. you can taste and learn about the countries and food and cultures in a fun and educational way that even preschoolers can enjoy!!
day 3 MGM
Also known as the Disney Studios this is a real working TV and Movie Studio also a theme park!!! First, split off. Dad and ds13 go on Tower of Terror and RocknRollercoaster while mom and ds3 do Playhouse Disney live, an interactive show featuring Rolie Polie olie, pooh bear, and Stanly Then hit the Little mermaid, Beauty and the beast and other disney classics. then see who wants to be a millionare Play it with the whole fam!! Make a reservation to eat at the Sci-Fi diner. It is a little pricey, but very cool. You sit in tables shaped like cars and the whole restaurant is like a drive in movie in the 50's. It is dimly lighted and sci-fi previews and old commercials play on the movie screen. It is a cool experience. Muppet vision live is a fun 3-D show but can be loud in some places. Ds13 will love Star Wars and Ds 3 can go nearby to Pizza Planet arcade and maybe meet woody or buzz there.
day 4
Animal Kingdom - Make sure to go first thing in the morning because it gets warmer than the other parks because of all the trees and stuff to make it jungle like inside. go to the back of the park fist to do Kilamanjaro safaris, which is like a ride through Africa. You are most likely to see animals up close early in the morning. Then you can catch some of the other highlights in the park. Camp Minnie/mickey is great for meeting characters and the lion king show and Tarzan Rocks show will entertain everyone. Then go to Dinoland, Ds 13 can go on the dinosaur ride while ds3 digs in the dino boneyard or plays on the massive play structure. There is also a wild mouse type rollercoaster there and a dumbo like ride (with Dinosuars of course. There is also a McDonalds in Dinoland, which we always seem to end up eating at because the food is familiar and a little cheaper than other places. If it is a hot day and you want to get wet, go to Kali River Rapids. You will get VERY wet. for the bigger rides, always use a fast pass rather than waiting in line. If the line says over 30 minutes it is usually better just to fast pass rather than waste your time.
I hope this helps. I am 10 - but I have been to disney 11 times. Read the guide books before you go and look at the maps> you can never be too prepared to do disney
Good luck
) and I would like to try the luau at the poly if it would be appropriate for DS. He likes pirates, star wars and anything playhouse disney. 
Oops.
