Basketball players should NOT be actors, just look at Shaquille O' Neill and Shazaam. That being said, Space Jam was a surprisingly fun film that combined live action and animation expertly, much like Who Framed Roger Rabbit years before. Around the time of the film, James Newton Howard has begun his slow rise to fame, gradually scoring big name projects. He ended up getting the job.
JNH's score for Space Jam is what you would expect from a film like this. The score bounces from the usual zany cartoon music to randomk bursts of Howard's trademark orchestral rises. For the most part, JNH's music is scored to match the film, so there really isn't any interesting thematic moments. Sometimes there will be brief moments of brilliance, with various clever ideas thrown into the mix (the rock theme for the Monstars really stands out among all of the cartoon music.) Unfortunately that's all you really get, folks.
After listening to the score and seeing the film, one has to wonder exactly why James Newton Howard was picked for Space Jam. The movie seems to be more in Bruce Broughton's territory, and as a cartoon composer he is much more adapt for a project like this. That being said, Space Jam is enjoyable if listened to as a cartoon score, rather than anything truly thematic or serious.