Star Wars (1977) - no comparison. Always No1 in my top 5 (the rest being Blade Runner, Alien, Gattaca and Macross:DYRL? and sometimes Akira)
You can bag it out for the 70s styling or acting, but everything about it remains magic to me. From the opening title scroll and the pan down to the rebel ship being chased by the Empire, through to the assault on the Death Star, it was truly 'epic' in the real sense of the word.
Ralph McQuarrie is the only sci-fi designer I like more than Shoji Kawamori.