Seeing a cartoon world in your dreams or seeing cartoon-like people suggests that your unconscious is sending up messages which are telling you something about the way you perceive the world.
The cartoon people, or cartoon characters, suggest that you may perceive yourself and those around you as comical or as not having much validity or seriousness. Your perceptions may be somewhat off due to your inability to look at the way things really are. Your mind’s eye distorts things so that you are more comfortable with what is going on around you.
If your world is full of stress and this dream made you laugh, consider the compensatory nature of it. In your dream you may be able to obtain moments of lightheartedness and fun.... The Bedside Dream Dictionary