Can you give me any insight into the Jewish perception of fun?

The word fun is a tricky word. If by saying fun, you mean parties, drinking, clubbing, watching soap operas on TV or any other forms of wasting time on nothing productive, so Judaism has nothing with that. These can be ether prohibited or only highly not recommended, depending on the nature of the activity and the person asking. If by saying fun you mean happiness and joy, here Judaism has a lot to say. Happiness is a basic fundamental concept that is not only recommended but embodied within the very essence of the worship of G-d. The Torah [Dvarim 28 47] relates all the bad things for not being happy with our lives and service of G-d. This is not even the tip of the iceberg for the concept of Jewish Fun = Simcha, the Chasidic teachings among other Jewish teachings elaborate in length on these issues.