“What kind of lunatic would make a movie like this and ask someone to invest in it?” asked Warren Beatty, reached by telephone recently at his home in Los Angeles. It was a rhetorical question, since the movie he was talking about was “Reds,” the three-and-a-half-hour historical epic he wrote (with Trevor Griffiths), directed and starred in 25 years ago. [The movie is being released as a DVD for the first time.]