Which one is "the gameboy one", by the way? The first Zelda game I played was Link's Awakening, which I still think is awesome, but I think a lot of people disagree with me. (I also hated Link to the Past, but I like every other one I've played) There are other games for the various gameboy platforms, though, as I understand it.So I'm wondering, what's the draw for Zelda? I tried playing the Gameboy game years ago, and I couldn't get myself into it.
As to why... I don't have quite the hardon for the series that others seem to, but I don't think its success is anything too magical. It just has good character design, good level design, and tends to have good graphics and music (Miyamoto makes successful series; I don't find Zelda too special apart from others). Link is cool, Zelda is pretty, the gameplay is easy but very interesting. And it hasn't changed very much, but hasn't gotten stagnant -- at least, not enough for the market to notice.