Yul Brynner did an entertaining job of portraying a ruler with certain idiosyncracies. If you read the book (under a different title - "Anna and the King"), it is indeed somewhat of a departure from the movie's muscial version. However, the movie is still a nice escape and can indeed be included among musical classics..
The King and I ..I found to be one of the most romantic movies of all time and to date my favorite. Yul Brynner and Deborah Kerr show you how movies use to be made. Musicals lift the spirit and make people happy. We need more of that today.