Finding Nemo is a good example of Physical Journey, one that I actually never gave much thought to when researching for supplementaries.
You have to explain the link involving physical journeys and the usually positive outcome (spiritual, physical, mental growth etc), and there are several examples from Nemo that are relative to this link. "The journey is the reward" is a good start to analysing this text. For example: Marlin is a completely different person at the end of the film, when he loses his fear of the microcosm surrounding him after finding Nemo. In a way, the journey was really making him find himself as well as his son. I can't think at the moment. Will be back later.