Zelda 1 on NES and it was hard. I don't remember ever getting past the 2nd dungeon. I still enjoyed playing it any chance I could. We didn't have many games growing up, so I wasn't exposed to much of the series after that until The Wind Waker/Ocarina of Time Master Quest pre-order bonus.
I do remember seeing a bunch of characters on the N64 box, among them being Link, and I was always curious about what a modern Zelda game was like but for some reason, my brother just had no interest in it at the time.
I didn't really play either game much until I was able to purchase them myself, but I do remember playing Wind Waker but never being able to finish it, because I either kept getting stuck or just couldn't play anymore since it was my brother's Gamecube.
My first proper Zelda game however was The Minish Cap on the GBA and I didn't get to beat it until much later. But by then, I was already a fan of the series through my brother. The first console Zelda game I would own and beat was Twilight Princess, though and immediately after that one, I jumped into Ocarina of Time and beat that, too.