Research topic

I am into animations so much! Therefore, for my research topic, I wanna research animations.
Most people think animations are created for children. I  only partly agree that.
"Up" is one of my favorite animation movies. I brough my niece, 6 years old, and a few her friends to see that movie. At the and, almost every female adult cried because lots of plots were emotional and we understood what these plots want to express. However, my nicec and her friends asked me: why do everyone cry?  Children feel that this movie is happy becuase the goal is achieved ,and the process of adventure is exciting. That are reasons children like this movie, but these are very different from what adults feel. 
Many animations imply deep meanings which are concerned about adult issues or real social problems, or some of them involves adult humor.  All of these absolutelty cannot be understand by just 5 years old kids.  So, actually, animation reflects real society. Another one, SpongBob is also a very popular animation seires in US, but it actually includes lots of adult humor which children cannot get. Some of this adult humor are not suitable for children.
Therefore, I want to use "Up" as a case to deeply understand what points about adult issues or social problems this animation reflects, or I could use "SpongBob" as a case to research how SpongBob reflects adult humor.  I haven't decide yet.