I feel like I have played so many in my life it was really hard to pinpoint one but I think I figured it out. When I was 13 my Dad on a trip to DC after my Mother and he got divorced many years before bought me a game in Japanese called Bushido Blade. I remember playing it by myself a lot and one day he sat down with me and we played for an hour. I made my summer.
My mom had moved me to NC a few years before so all my old friend's up in DC had moved on and made new friends and had jobs. I was pretty lonely too be honest. So that time with my Dad playing a Samurai game was a huge deal to me. I liked it so much I later collected a bunch of old Samurai movies and games and even a sword or two.