I first remember seeing "The Man Called Flintstone" in 1968 when the elementary school I attended in Warren, Michigan obtained a 16mm print of the film and ran it as an "after-school" movie, complete with popcorn and soft drinks. (My folks never had the time to take my younger sister and I to see it at the theater, but then, in 1966 I was only 4 years old.) Cartoon Network's Boomerang channel ran it a couple of months ago, and it was certainly a treat to see "The Man Called Flintstone" again after so long.
I do agree, the movie's opening with Wilma as the Columbia Pictures torch lady was a riot; her torch exploded into the opening credits. Sadly, current television prints have deleted this opening, since Hanna-Barbera first became part of the Turner Entertainment empire in 1992 and is now a part of the Time Warner empire; Warner Bros. Television now syndicates this film (Sony Pictures Television ceased television syndication of "The Man Called Flintstone" in the mid-1980s). I highly doubt that opening will ever be restored, even if the movie ever appears on DVD.
And I never knew that was Henry Corden, the future voice of Fred Flintstone, singing the duet with Mel Blanc as Barney. I recently discovered (according to a Goldmine record collectors' guide) there was a soundtrack album of "The Man Called Flintstone" - on HBR Records (Hanna-Barbera's record label), naturally - but it is very hard to find. If and when I ever do locate a copy, though, it'll certainly have a place in my record library (I recently found a copy of the soundtrack album of "Hey There, It's Yogi Bear," Hanna-Barbera's first movie musical, and that album is even harder to locate)! Notice to collectors: extant copies of the soundtrack of "The Man Called Flintstone" command $50 and up, depending on the condition of the vinyl (good luck locating it).
I can also hope Warner Home Video will strongly consider putting "The Man Called Flintstone" on DVD soon!