Not inappropriate for children, but unlikely to appeal to them
I love this movie. Why I love it is difficult to explain. It's much more than just a movie about a big dinner where everyone discovers the joys of eating. It's a movie about relationships, where things that are said have little meaning, but things that are not said speak volumes. People's facial expressions, gestures and microsignals convey a depth of emotion that cannot be fully understood in one, or even two or three viewings.
I wouldn't stop any children from watching it, but they most likely won't understand it and will sleep through most of it. It has some cigar-smoking (by the military officer) and some alcohol use (a lot during the dinner).