1982 - First major use of CG - Tron. The movie was way ahead of its time in many ways. The sequel coming out late 2010 is gearing up to break new ground visually as well. And to think, a Nintendo DS is three times as powerful as the multi-million dollar computer they used to create the visual effects.
1993 - Dinosaurs - Jurassic Park. To think digital dinosaurs almost didn't happen. They already built the stop motion dinos and did screen tests, and this is what Jurassic Park would have been had it not been for CG artists staying up late working on a side digital-dino project. Once the filmmakers saw a test of a CG dino attacking the Jeep, they scrapped the stop motion dinos immediately.
1995 - First full length CG Movie - Toy Story. Disney makes the first feature length cartoon, then they do the same for CG. Not only that, it was a wonderful story with timeless characters.
1999 - Bullet Time - The Matrix. I only like Superbowl because of the food, friends and commercials. Once I saw the teaser for The Matrix, I was like a deer in headlights. Once the movie came out, the rest of the world was too.
1999 - Gollum - Lord of the Rings. While a extremely convincing character with extremely well done facial movements (see the Gollum monologue scene), he still feels like a CG character when acting with real actors in much the same way JarJar Binks felt in the Star Wars prequals. At the time, it was the best CG character yet.
2006 - Davey Jones - Pirates of the Caribbean: Dead Man's Chest. While Gollum will most likely get the praise as best CG character, I would argue Davey Jones was much more convincing, realistic, and fit much better into the scenes than Gollum did.
2000 - Final Fantasy. The movie completely stunk, but this was the first film where in some of the scenes you felt the places and characters were actually real. Mute the movie and make up your own story when you watch it, as whatever you create will be better than the actually storyline of the movie.
2007 - Perfectly seamless CG - Cloverfield. The movie was made for 25 million, but looked like a 150 million movie. Not only a visual masterpiece, it was brilliantly produced, marketed, directed, acted and edited.
2009 Avatar. James Cameron, super HD 3D cameras and the most convincing use of motion capture so far. You can see nearly every emotion on the characters face which was acted by the actors. Too bad all of his effort went into the technology and not the story.
