As much as I love Link's Awakening, I doubt it can be called the "Best Game Ever", as in all games ever created...ever... LA is in my opinion, one of the best Zelda titles, but it still isn't "the" best Zelda, which already puts games like Wind Waker and Ocarina ahead of it, just in its own series of games. I haven't played the majority of games out there that some may consider the best, such as the Final Fantasy games, just because I'm not real big on vast RPG titles. I find myself very bored with games like that.
So no, LA probably is not the best game ever. Best handheld game ever? That would be much more likely.