I would do Epcot instead of MGM, but I just am not crazy about MGM, either! At Epcot, she would probably enjoy both of the boat rides in WS (Norway and Mexico, if it is open when you go), Journey into Imagination, and Nemo/Living Seas (DD2 loved the fish and other sea creatures). Those come immediately to mind, and there might be others. At MGM, it seems like it is mostly shows, which I'm not personally crazy about, and my 2 yo didn't seem that crazy about the shows, either. There just isn't as much to do (for you or her) at MGM compared to Epcot. If you like WS at Epcot, you can stop with DD2 to see some of the performers. DD2 was very entertained by one of the performers in Italy.
Regarding character meals, DD2 loved the "face characters" like the princesses, but, other than Mickey and Minnie, she wasn't crazy about the other characters. I was very surprised that she didn't want to see Pooh, but those big characters scared her (Goofy and Tigger are very big).
Enjoy!