"Bambi vs. Godzilla" takes its title from a two-minute animated short (actually "Bambi Meets Godzilla") in which the monster crushes the innocent little fawn. This would make a fine metaphor for the way the film business treats artists if it didn't mean miscasting Mr. Mamet in Bambi's role. As the lacerating essays in this uneven but icily hilarious collection make clear, he is far better suited to stomping on Tokyo.