Dr. Dolittle 2 is an interesting comedy that is generally funny because of its various references to other films and the presence of Eddie Murphy.
The plot is fairly simple: An area of land near the San Francisco bay is about to be razed threatening the lives of all the animals who live there. The animals, appeal to Dr. John Dolittle (Eddie Murphy), a doctor who can communicate with animals, to save their environment. He comes up with a plan that involves the mating between two rare Pacific bears, and propagating the endangered species. The problem is that one of the bears, Archie (voiced by Steve Zahn), is a circus bear who is not exactly father material. Dr. Dolittle is given one month to accomplish the re-integration of Archie into the wild or the face the destruction of the natural habitat of his beloved friends.
It is the animals in the movie that are the stars of the film, but Murphy does nicely complement their antics without overacting. The humour level in the film is consistently high. The animal/human interaction is executed in a clever manner which makes it seem as though as animals indeed can organise (into an union of actors, that is). The voices (done by people like Steve Zahn, Norm McDonald, and Lisa Kudrow) are what make the film work.
Dr. Doolittle 2 is a fun movie to watch with amusing references to The Godfather and The Terminator. I highly recommend checking it out.