[quote name='jwk94']You actually won't be able to do that without being in the game's Toy Boy Mode which is basically the "create mode."[/QUOTE]
The designers claimed that "putting tracks for the Cars characters in every world would be silly", and that "playing as Mr. Incredible in Pirates of the Caribbean ruins immersion".
True, but for comparison's sake you can bust out any Skylander in any level without any silly restrictions. I know they chose to make it so that characters can only interact in their own worlds and that they can only interact with other franchises in Toy Box mode, but it's still ridiculous. Disney is notoriously restrictive with their franchises.
Personally I want to see Ralph wreck some Omnidroids, Davy Jones brawling through the Lone Ranger playset, and Jack Skellington clambering through Monsters University.