okay, here's my take, im starting with N64
Ocarina Of Time - is a classic in every sense of the word. At the time it was easily the best game out and if you never played but call yourself a hardcore gamer I seriously have to question that. However, if you never played it but go back to play it now for the first time, you might not like it. The gameplay moves kinda slow and the controls are dated, however the story is epic so its worth checking.
Majora's Mask - this is my favourite Zelda game and aged very well. It used the same game engine as OOT so it plays in much the same way but there is alot more going on to keep you moving. The general story is more basic but the 3 day time limit/time reset theme works extremely well to create alot of dimension and urgency, plus it throws you straight in rather than build slow like other Zelda games. My wife never played any Zelda game before but she really enjoyed this one. If you only ever play one Zelda game I would recommend this.
Wind Waker - This is a really great game and a little different than other Zelda games. Its cartoonish but the gameplay is great. The overworld in this is one of the best out of the series but it really creates a great mood. I would recommend this but I probably wouldn't use it as an example of Zelda mainly because it did seem like a slight departure.
Twighlight Princess - I thought this game was dope. To me it seemed like the perfect mixure of OOT and MM. In alot of ways and seemed to play like an updated version of OOT in exploration and in the way it deliveres the story but I prefer this to OOT simply because the controls and gameplay are alot smoother and exploring the overworld is more rewarding. also, little things like travelling between regions and fighting enemies is just alot easier to do, plus the dungeons are some of the best from all the Zelda games. It was also very dark with the story and had an urgency that reminded me of MM. I understand how some folks might not have enjoyed it so much because it was very similar to those earlier titles, but i still think it was a great game.
Skyward Sword - I really had alot of fun playing this game for a number of reasons. The story is really enjoyable and the game moves pretty quickly, but it is the controls which really set this game apart. Playing this game is just fun because it uses motion control perfectly, perhaps the best controls I have ever played in any game of any genre. It is hard to explain but it feels so intuitive it just plays really really well. My major fault with this game is the lack of a free-roam overworld made it feel a little boxed in, so the exploration that was so great in Twighlight Princess didn't really exist here, however each area in the game is so large it made up for it. So instead of having alot of different little areas and dungeons connected by a huge overworld, it had 3 massive areas filled with a lot of things to do, so the game was less about exploring and more about playing figuring out each area.
Its just important to note, Zelda is an acion adventure game, not an RPG, which people often mistakingly compare it to. As far as the stories being similar, its because the premise of LoZ revolves around the concept that there is a good spirit (Zelda) and bad spirit (Ganon) and a hero of time (Link) and they are battling for control of the world and are being re-incarnated over and over again so each game (aside from MM) places these three spirits in a new scenario/time in which you play. Its not for everybody but yeah, if you like action adventure games you are definitely missing out.