The pilot episode, "An Unearthly Child" however is top notch and as good as just about any other piece of Who. Very dramatic and very effective in setting up a mystery and dramatic tension and then ably explaining it all in easy-to-understand terms. I absolutely love that episode.
And watching the rest of it in episode format daily made me enjoy the rest of the story more than I usually do, especially once I get past the caveman limitations inherent in the story.
William Hartnell is fantastic as the Doctor. Far from the lovable grandfather figure he would later become, he is almost the antagonist and villain of the piece. Threatening Ian and Barbara often throughout the story and then kidnapping them. Forced to team up to survive the Doctor throughout the story, he seems only concerned with his own well being and that of his granddaughter Susan. He even goes so far as suggesting they commit murder to survive and it appears as if he is going to go through with the act before Ian stops him.
Carole Ann Ford is also very good as Susan making the most of playing a normal teenager at times and at other times seeming a bit otherworldly. An aspect of her character mostly played down in later stories unfortunately.
William Russell and Jacqueline Hill as Ian Chesterton and Barbara Wright are not only the audience identification characters but the real heroes of the story as well. Its them we wind up rooting for mostly and in these early episodes they are just as much the leads as William Hartnell is.
Not the best story even watching it in episode format but it has much going for it still mostly due to the interactions of the four main characters. I give it 5 out of 10 TARDISes.