Hi! We just got back from WDW yesterday. Wednesday we took our 4 year old twins and almost 3-year-old to MGM. They liked it. There wasn't as much for them to do there as at MK, but we still had fun.
They LOVED they Disney Playhouse show.
Also LOVED the Play N Dine character meal at Hollywood and Vine. Out of the 4 character meals we did, this one was their favorite. Lots of character interaction. I would highly recommend it.
I tried taking the twins to the Muppets 3-D movie, but it scared them so we left about 5 minutes into it. Didn't even attempt it with our 2 year old since MIckey's Philharmagic scared him.
They didnt' want to see The Little Mermaid show since they're scared of Ursula.
I took just one of my twins to The Beauty and the Beast show (the other two kids were tired and stayed at the resort with Daddy), and she loved it. It was a really neat show.
They also really liked the character interactions: we met Lightning McQueen, Mickey, Buzz Lightyear, Woody, Jessie, Green Army guy, Jasmine, Alladin, Jafar.