Return of the King is the only fantasy movie to ever win an Oscar in one of the top categories. They give the technical awards to fantasy/action/science fiction all the time. Terminator 2, Matrix, and Jurassic Park all won multiple awards in categories like special effects and sound. Going into last year's Oscar, it was obvious that Return of the King was going to win Picture and Director, but winning Adapted Screenplay was what shocked me. And yes, Fellowship should have won Picture instead of Return, especially since I consider Beautiful Mind(which beat Fellowship) to be trash and thought Mystic River(which lost to Return) to be great.
The Academy and other critics don't consider acting in fantasy, action, or comedy to be as important as drama. Some of that acting requires very little(Steven Seagal and Jean Claude Van Damme having careers is proof of that). However, there are great performances in those categroies that are every bit as good as the dramatic work the Academy and critics praise. They only nominated Ian McKellan(for Fellowship) out of the Lord of the Rings series while I think many of those actors, with a few exceptions, gave the performances of their careers and there should have been multiple acting nominations for each of those films. Same goes for Star Wars. Alec Guiness was nominated, but Mark Hamill and Harrison Ford also deserved nominations for the first two films. That was all I was saying about Ron Pearlman in Hellboy. He gave a performance that I think was better than just about any other actor could manage in that movie. If they gave the part to DeNiro, I think he may not have given as good a performance as Pearlman. That is what I meant by a performance on the level of performances of actors getting year end kudos.