"Realistic graphics" shouldn't be a poll option. No Zelda game, not even Twilight Princess, has had an even remotely realistic art style.
Anyway, out of the Zelda games in existence, I prefer the more colorful styles, specifically Ocarina of Time 3D and Skyward Sword. Zelda is a whimsical fantasy series, and dark pallets like that of Twilight Princess just don't suit that. Those kinds of art styles are more akin to series like Silent Hill. Zelda should always have vibrant colors to fit its whimsical tone. That's not to say it should always be cartoony, but it's absolutely saying it should never be dull.