Seth Macfarlane relaxes by sitting in his tasteful mansion, listening to big-band albums, watching old musicals and playing piano; he works by sitting at the kitchen counter and scribbling fart jokes. The creator of the animated, highly offensive Fox TV shows Family Guy, American Dad! and The Cleveland Show throws enormous Gatsby-like parties at his house and books a full orchestra. He is polite and thoughtful, with an easy laugh. It's as if you walked into the offices of Mad magazine in the 1960s and found out the editor was William F. Buckley Jr.
MacFarlane, 38, is visibly happy as he...