Elle, I have seen them all and between the ones you are thinking about, I recommend Arang and the Magistrate, followed by Iljimae and then Scholar Who Walks the Night. Arang was my favorite of his until Moon Lovers took its place. He and Shin Min Ah have the best chemistry! Iljimae is a classic and of course he is awesome there too but it has no romance to speak of. Scholar was really good, though there were writing flaws and the female lead was really off imo. However, Lee Joon Gi as a sexy vampire is not to be missed!
Hope I was helpful. (*^_^*)
