Kaepora Gaebora is the most annoying, I hate that guy. I still, to this day, hold down a button to skip all of his dialogue then end up asking him to say it all again. What annoys me even more about him is even if you remember where the option for "no" was last time, they switch around or even sometimes change the meaning of the question, thus making no, yes and yes, no. D: He wouldn't shup up either. Luckily I know how to avoid him at some areas so that I don't have to read him yap on about everything I already know.
And you haters need to stop hating on Navi, most people are doing what I did when I first joined a forum and just joined in with the hate because that's what every other noob in the community hated. She barely makes you have to listen to her, once you leave the Great Deku Tree, I am sure that she doesn't interupt against your will. If you are getting sick of listening to her say random crap about enemies...etc, stop pressing the god damn C-up button and all will be fine.