As another IMDb'er has mentioned, this film is one spectacular visual moment after another, but unfortunately with really terrible sound. The reason for the bad sound is that the film was produced at Cinecitta studios in Rome and at that time, all films there were shot without live sound. Everything was dubbed later: dialogue, music and all ambient sounds. In addition, recording facilities in Italy were primitive (this was only 11 years after the catastrophe of WWII), resulting in the canned quality of most of the dialogue. (One of the reasons Antonioni's films were such a breakthrough in the following decade was his use of live sound recording and location shooting).
Anyway, War and Peace is a most worthwhile film experience for Vidor and Cardiff's Technicolor Vistavision visuals, for the screenplay which is often quite beautifully written, and for many fine performances from some exceedingly charismatic film actors, especially the astonishing Audrey Hepburn. There are close-ups of her that will make your heart stop.