Hi, Traci!
Wow! There have been some changes since you last visited Walt Disney World, so I'll try to highlight the must-dos that are new for you.
First, be sure to set some time aside for
New Fantasyland in Magic Kingdom. Don't miss Under the Sea-Journey of the LIttle Mermaid, Enchanted Tales with Belle, Ariel's Grotto, The Barnstormer and Dumbo the Flying Elephant; be sure to visit Gaston's Tavern for a quick bite to eat and have lunch at Be Our Guest Restaurant (if you can snag a Table Service Advanced Dining Reservation there, be sure to do so!) Also be sure to have a great viewing location for Celebrate the Magic a spectacular projection show which uses Cinderella Castle as its canvas. (We prefer to stand in the Castle forecourt.)
Over at Epcot, don't miss the newly-reopened Test Track, as long as your little one meets the 40" height requirement. Check out Disney Phineas and Ferb: Agent P's World Showcase Adventure, too, as you tour World Showcase. Disney's Animal Kingdom features Finding Nemo-The Musical, a great, unique show unlike anything you'll see elsewhere.
Your kids are now older (and taller) on this next visit, so there may be attractions they weren't able to enjoy previously but now can. Keep an eye on the height restrictions, but have fun considering your options!
For dinner? If you are unable to get an ADR for Be Our Guest Restaurant, consider Epcot's Chefs de France, Rose & Crown Pub, San Angel Inn Restaurante, Teppan Edo, Tutto Italia Ristorante and Via Napoli Ristorante e Pizzeria. Try Mama Melrose's Ristorante Italiano at Hollywood Studios and Tusker House at Animal Kingdom.
There are lots of great options at nearby WDW resorts and Downtown Disney, too, so send me another question if you'd like to hear about them, Traci!