TOD:
I don't know that I've ever seen a play that I saw later as a movie. But there's two movies I can think of that are basically filmed plays that I enjoyed very much:
Come Back to the Five and Dime, Jimmy Dean
A Case of Libel
I loved Jimmy Dean, Jimmy Dean. Great cast, fun melodrama.
Did you see the play or the film? I saw the play, which I thought was dreadful: every character had to have their revelatory moment so the last act was a lot of cheap desperate scenes of over-emoting, Sandy Dennis was her usual bag of ticks and tricks, Cher had no idea of what acting was since you can't piece together a live performance, but i did like Sudie Bond and Kathy Bates.
I couldn't wait to get out of the theatre. I forget which theatre it was now. The Martin Beck, maybe?