Hidden Town for me - I like how there are three things in there that can be acquired, not just one or two. Also, I like the town location.
Spell spell - IMO, the most useful/helpful magic in the Valley of Death, with or (especially) without the Candle & Cross. Magic Key - too bad it came late in the game and not even really necessary to complete the 6th temple. Final Magic container.
Fire is basically useless, and you're usually at full health when you pass by it (after completing levels 3, 4 and 5). So no real need to even step near it.
The bigger mystery is why Ruto got no votes. Jump is a required spell and it has Error! --- In the beginning you will see a black square. This is actually a cave. Make Zelda walk into the cave and get the Brown Sword. The rest is easy if you have it.
Jump, Fairy, Reflect, and Thunder are all needed to beat the game. Spell is needed to beat it unelss you want to repeatedly grind for potions. Shield and Life are very useful spells. But Fire is a pretty much useless spell, plus there's nothing else special about Nabooru, plus you can get from there to Mido (and vice-versa) with only one or two battles.
So the town Nabooru is pretty much useless, and you lose very little if you completely bypass it. --- Nagas on a plane! ^_^