It's a scifi movie about this blacksmith who goes to slay a dragon and falls in love with this queen or something. But then he drinks some potion and falls in love with another woman. Anyway the ending is sad and I think someone dies, I can't remember. Does anyone know what I'm talking about?

Sounds like Curse of the Ring (http://www.imdb.com/title/tt0387541/) or one of it's many versions: Movie connections (http://www.imdb.com/title/tt0387541/movieconnections)

That's a good movie.AT the end the dragon slayer and the queen of Iceland dies. Its called " The curse of the ring"