animations on gui

So this is my first game I'm making using unity and I've been working on it for a while now. I want the story to be told through windows that pop up with the characters faces and dialogue below them. But how would I go about doing this? I can make images of the character and animate them to cycle through them to make it look like hes talking but how would I put this in gui and how would I put gui below it? Thanks to anyone who helps.