Here's a rundown of the playable characters from the 1.0 set:
Mr. Incredible, Jack Sparrow, and Sulley are part of the starter kit
Additional Incredibles characters: Elastigirl, Violet, Dash, Syndrome
Additional Pirates of the Caribbean characters: Barbossa, Davy Jones
Additional Monsters University characters: Mike, Randy
Cars: Lightning McQueen, Mater, Holley Shiftwell, Francesco
Toy Story: Woody, Buzz Lightyear, Jessie
The Lone Ranger: The Lone Ranger, Tonto
Wreck-It Ralph: Wreck-It Ralph, Vanellope
Frozen: Elsa, Anna
Phineas and Ferb: Phineas, Agent P
Additional Characters: Rapunzel, Sorcerer's Apprentice Mickey Mouse, Jack Skellington
What's interesting is that a number of characters have their original voice actors. Clearly they managed to get Idina Menzel and Kristen Bell while Frozen was still being made, but then you have a good chunk of the original voice actors in The Incredibles present like Craig T. Nelson, Jason Lee, and others, so it's fun to hear them with a few new lines of dialogue to add.
At present, Incredibles, Pirates, Monsters, Cars, Toy Story, and The Lone Ranger have playsets, which are like story modes to acquire new pieces to add to the toy box.
2.0 will be released this fall and will introduce the Marvel Super Heroes to the game.
The starter pack will include Iron Man, Thor, and Black Widow with Captain America, Hulk, and Hawkeye having to be picked up individually. Just recently they announced Maleficent and Merida as playable as well. While not confirmed as playable, folks have noted the presence of Stitch and other Marvel characters such as Spider-Man, the Guardians of the Galaxy, Nick Fury, Loki, The Green Goblin, and others to be introduced in the 2.0 launch.