Not Bad...but could be better...
A lot of the problems have already been mentioned. While some of the animated movie clips are fluid, the problem in most of the movie, all your characters are doing is standing still. For some pieces, an author can get away with it or better yet, use the static forms to tell a storyu. The song that this Flash uses is both short and fairly energetic. This is a Flash that should be more hyper, and while you made good direction choices given the material, you need more material. For instance, that running shot of Link is horrible. Also a litte shading couldn't hurt either, or some better backgrounds
With sound, I think the problem is that you can add a few sound effects that wouldn't take away from the song. Making a pure music video means that the visuals have to line up with the song exactly, and that can be VERY hard even for trained professionals. Adding a sound effect won't hurt a piece, and can help mask the moments where the action is too fast or two slow for the song.
Obviously, though, you can draw and animate well, which is why this review is a little harsher than I would normally make it. Perhaps it would be better if you didn't use Link on the play screen. Otherwise it gives raises people's expectations, then disappoints them.
BTW, I did like the part where Link threw his sword. That was a very nice old-school touch.