'The Sign of Zorro' is good fun.
I've always heard of Zorro, with his famous mark et al., though have never seen anything directly about him. This makes for a strong first impression. It is a compilation of a number of the television show episodes, but it's edited together nicely to the point I didn't even notice.
Guy Williams is great as Zorro, bringing the required amount of charisma and smartness to the role. Henry Calvin is also impressive, as comedic character Sgt. Garcia - he gives the laughs. Britt Lomond also gives a notable performance, as Monastario. It's all well acted in general.
I have nothing negative to note, everything makes for entertaining viewing.