Unity 5 game intro

I wanted to do an intro for my game, and many said, that the best way of doing that was to get a plane in a scene, and apply a video texture to it(the intro video). I'm using unity 5, and the inspector always crashes when I want to import my file. I've tried many file formats, and nothing works. Is it something unity 5 does not support yet, or am I doing something wrong?