Well, for it's time - it was pretty amazing. Graphically speaking, I was impressed. I was also impressed with how long the game lasted - all the environments, all the quests, and it all fit into that cartridge. I was a pretty young gamer back then, I got the N64 when I was 10, and the Ocarina of Time was the first game for me that had an epic feel (it was also the first Zelda game I ever played) and felt expansive. In short, it was the first game that, to me, felt like it contained a WORLD, and I can tell you, a 10 year old kid is impressed by that.
Looking back at it, I am still impressed with it, and I still recall having a lot of fun (as well as frustration, especially when stuck in certain areas). Had I played it when I was older, would I have had as much fun? Yeah, I think so. For me, it was a really ground-breaking game - I had never played anything else like it.
But hey - not everyone likes it. If it bored you, it bored you. And that's just fine. Maybe you had played other, better games before hand. Or maybe your expectations were hyped. Or maybe you didn't like the game mechanics or the thematic setting or the story. No one has to justify why they don't like a game. If your friend gave you verbal abuse just because you didn't like it, then nuts to him.