I have to preface this list by noting that by no way am I a connoisseur of martial arts films. It is also hard for me to objectively rate them, so I went the other way and rated them as subjective as I can, including their impact on me at that particular stage of my life.
(1995) The fight in front of the prehistoric park. I love this fight because, besides the humor, it was really time for Tommy and Richard to unload on one another.
(1980) All the bouts. I saw this film right when I got into college and it was the first time I saw how brilliantly Scorsese was able to use elements such as lighting, framing, film speed, sound, and editing to enhance the dramatic beats of each fight.
(1991) Jet Li's ladder fight. I was in film school and I remember driving with my friends to Alhambra to this Chinese theater to catch this film. It was the first time I saw wire work with the camera moves like that and it blew me away.
(1978) Bruce Lee's fight with Kareem [Abdul Jabbar]. I remember seeing this as a kid and it made the wait through the fake dude all worth it. I was a huge Lakers fan and had no idea Kareem was even in movies. The huge foot print on Bruce's chest is still classic.
(1973) All Bruce Lee's fights. Growing up in the '80s, I was first introduced to martial arts films through the Kung Fu Theater that ran on Saturday afternoons. Of course, the TV stations bought the cheap films to fill the air. So I was actually introduced to Bruce Li, Bruce Lei, and those guys before seeing the real person. It was through the advent of the VCR that I was introduced to the real Bruce Lee. And holy crap! He was a million times better than the other guys. His intensity, complexity, sexiness, and a sense of empowerment were traits I had not seen on screen of an Asian/Asian American character prior to him.