Hi Lorena!
Well, the MOST recommended park is the Magic Kingdom! For your 3 year old and 10 month old that one will be the most Mickey-Mouse, the most Princess-y and the most exciting! Some of my kids favorite rides (they are 2 and 5 now, but have been when they were babies, too!) are Dumbo, Mad Tea Party, Philharmagic and Small World in Fantasyland. In Adventureland, the kids liked Swiss Family Robinson Treehouse and Aladdin's Carpet Ride. My son (newly 2 at the time) loved Country Bears in Frontierland!
Second to Magic Kingdom, I'd vote for Animal Kingdom because there are so many great shows, interactive adventures and animal encounters. Your kids will be enthralled from start to finish, I promise!
My third choice is Hollywood Studios because of the Disney Junior Live on Stage where you get to see all your favorite Disney Junior characters--including Jake from the new Jake and the Neverland Pirates!
Also, check out the
Magical Beginnings Map to see more kid-friendly suggestions!
So excited for you guys--you're going to have a blast with your little ones!