I'm not even sure what the first martial arts film I ever saw was.
With a lot of films or genres, I can tell you where my interest began, but with martial arts movies, it's not that easy. All I know is, I have always had a deeply-seeded love for watching dudes kick the ever-lovin' crap out of each other in the movies.
It's strange that it doesn't translate to real life. MMA fights and ultimate fighting and even pro wrestling... that stuff does nothing for me in a real-world context. But movies in which guys bust out the same skill sets and battle? Count me in.
Like most martial arts fans, I'll sit through a whole lot of crap in a movie to get to a great fight or even just a couple of great moves within a mediocre fight. And when you see someone who can handle themselves fairly well on-camera, doing it as real as possible, it's exciting. It seems like every few years, there's a new guy or a new country with a new industry, and we gets lots of potential new movie stars, although of course, not all of them connect in the long run.
The reason Bruce Lee was one of the most amazing movie stars (which is something totally different than an actor) ever was not because he fought well, but because of HOW he fought well. Bruce Lee was intensely aware of the camera and how he looked when he was running through a fight. He thought like a filmmaker.