To me, it doesn't matter which one is my "first" Link. If that was the case for everyone's vote, then we basically don't have a choice on which Link we get to pick since apparently our first Link will forever be our favorite...
Ocarina of Time Link was my first, but Twilight Princess Link is amazing to no end. XD
Ocarina of Time was what hooked me to the series but Twilight princess in my opinion was a little better graphically, story-wise, and how they took and expanded on some of the elements in Ocarina of Time. I sometimes find myself playing Twilight Princess more than Ocarina of Time. I will agree though that Ocarina of Time was a lot more difficult when it came to the dungeons.
OoT Link was my first Link, and I find it cool that he's essentially the most famous within the games. He's a legendary figure and you can really feel that when he's brought up in the games following OoT, especially the opening for WW. Overall, I feel that his story is like the Zelda equivalent of Greek heroes like Herakles. But within his actual game, he's not very interesting.
TP Link had a more defined character and actually showed emotions. Even though you don't really learn anything about his backstory, there's enough information given through dialogue that you get a better idea of who he is. The relationships and conversations also don't feel as one-sided, even though Link doesn't talk. Then there's the fact that I just like his design a bit more.
I like both of them a lot, but I'd have to say I like TP Link a little bit more, just because you see him more as a character and thus is a bit more interesting.
Ocarina of Time Link is definately better. I don't mean graphics/design quality, of course. But I think OoT Link looked cooler and more heroic than TP Link. Of course, I mean Adult Link, not Kid Link. In my opinion, there's nothing heroic about a kid who goes around wearing just a tunic and no pants.
OoT Link is THE legend of Zelda in my eyes. My favorite link is kid Link from OoT and MM, but the hero of time himself, both young and old, is a legend among legends. TP Link is great and I definitely think he would beat OoT Link in a fight, but... this is OoT Link. His game set the example for future Zelda and non Zelda games. He was in TWO smash brothers. Also, TP Link is based off of OoT Link, so he's really just a copy of the original. Again, not knocking TP Link, he's awesome too, just not the top dog.