This is an image of a Toontown Game Card. If you look closely, you'll notice that the duck has webbed feet, and the dog has a tail, despite the fact that they don't have either in-game.
Group of Toons (From Toontown Japan)
An image of a large crowd of toons from Toontown UK. The exact same image is used in the Installer video.
An image of several toons from Toontown's French website.
Two toons shaking hands. (From Toontown's French website)
A background image from an official Toontown social media page.
A background full of toons from the official Toontown Flash game called "TuneTown."