I have seen this film so many times over the years, having been introduced to it when I was about 10 by my grandfather, who was a true classic movie fan and grew up watching Errol Flynn on screen.
I have also seen the Kevin Costner version, which although entertaining in its own way mostly thanks to the amazing Alan Rickman, pales in comparison to this version. Heck, the Fox in the Disney version of "Robin Hood" and Cary Elwes as "Robin Hood Men in Tights" were better Robin Hoods than Costner! No, Flynn was meant to play this role.
The supporting cast is also incredible. Claude Rains as Prince John was priceless, and charming in his own malevolent way. Basil Rathbone, Alan Hale, Patric Knowles, and Eugene Palette were also memorable for me in the film.
And, of course, you can't write a review of this film without mentioning the chemistry of Flynn and Olivia de Havilland. Past or present, very few on-screen couples possess the natural chemistry those two had. They just looked at each other and you could tell there were unresolved feelings there (and there were, both admitted later on). They were just magic on screen together.
There is really something for everyone in this film, and I recommend seeing it.