If you click the link for the "Complete List" you'll recognize a number of well loved films in the list. Not many are heroic or epic fantasy with medieval themes though. And not a lot of blockbusters, although I was surprised by how well the "Mummy" movies did.
The first two Narnia films did decent. Willow got its budget back and more. The first Conan movie did excellent. Dark Crystal was a hit, and Labyrinth did decent. Eragon and the Golden Compass made their budgets back.
Really, Dragonheart was probably the biggest success.
But, yeah, there's not a lot of fantasy hits out there. And most (Pirates of the Caribbean, Dragonheart, Harry Potter) are kinda sorta set in the "real world" with a hint of magic. Or been based on a popular book series (How to Train Your Dragon, Harry Potter again, the Middle Earth films).
A D&D film is always going to have an uphill battle.
A good D&D movie would need to be on the very top of its game with spell and ability effects. It would need to harness the seriousness of the assigned goal (such as finding the Lich's Lair before he can used the kidnapped innocents in his experiments), but also keep the atmosphere light enough to not overstress everyone in the party (A kind of like "another day at the office" deal.) By no means should it feel like the adventurers are "taking turns" when they get in combat (I reflect back to the Doom Movie and how they tried the 1st person shooter thing), but it should introduce the differing types of creatures in the world. I am not speaking of the common "everyday, every story has one" centaurs. Try introducing a new species that fits your storyline, like Bullywugs or Kuo-toa or WereBears or WereRats. The actors would have to be diamonds in the rough and the CGI would have to be world class. I've seen a few of the already released D&D movies on Syfy and such and I found myself wanting so much more from them, both actors and cgi.
I saw Seventh Son recently, and it occurred to me that it might fit a lot of people's ideas of what a good D&D movie would be like. Take something of that scope and style, but use Forgotten Realms or Greyhawk lore, and it seems like it might work pretty well.