If a date is mentioned in the movie then it is easy to identify and categorize. For instance 2001 A Space Odyssey and it's sequel 2010 are no brainers. Some movies like Star Wars throw a wrench in my project. Did they really have cool technology, space ships, and robots a long long time ago. I wish he would have said way "in the distant future in a galaxy far far away" so I could have included Star Wars. Oh Well, I guess George Lucas is going to pay for that mistake now as I leave his series off my futuristic movie timeline.
Many movies that take place in the future do not specifically mention a date when they take place. Some of these are: The Matrix, Blade Runner, V for Vendetta, Gattaca, Waterworld, Starship Troopers, Equillibrium, etc. I think it is easier to play it safe and just say it takes place some time in the future than to give a specific date, but I'm glad the movies below did. If you come across any others with specific dates please add them in the comments section.
The 6th Day- 2015
Back to the Future 2-2015
The Terminator 2-2029
The 5th Element-2250
Chronicles of Riddick-2505
Now if you'll excuse me I need to go find something else to categorize.