My son has watched these since he was 3 and LOVES them. The same with my neighbor. My son even has some of the figures and 2 light sabers. The movies aren't really that bad. There's no fowl language. Other then the blowing each other up. But honestly, they have done studies on boys that show even in boys who are never given guns or shown what guns are about, they still turn sticks and things into swords and guns anyway. But read this. It is the parental guide from IMDB about the movie. And all the movies are the same as this.
http://www.imdb.com/title/tt0076759/parentalguide
He can hear and see worse then this watching the news.