I only discovered it about 15 years ago but it's been one of my favourite films since and I think it stands up remarkably well. The jokes are all still hillarious and the acting, camera work and set design is a lot of fun to watch.
It's technically B&W, but that was a stylistic choice to make it look like prior monster movies. It's not nearly as old as most B&W films that were made that way due to the lack or expense of color technology.