What kind of demented weirdo would call Star Wars "A New Hope"?
If you said to someone, "Hey I watched A New Hope last night," no one would have any idea WTF you were babbling about--it sounds like some kind of Christian self-help show from a women's-oriented little-known cable channel.
If on the other hand, you said "Star Wars," I suspect there's only one goofball in the world who would pretend not to know what you were talking about...