was a HUGE problem for me.
The other enemies? Well, those electric-bobokins (spellcheck) were a problem as well.
Huh... I think I also had trouble with Deku Babas at the beginning of the game. My WiiMote wouldn't let me hit them at the correct angle, so I kind of spent 10 minutes on each enemy.
Post Script: The spoiler is there to keep people who have not finished the game from being spoiled. Don't click on it unless you wish to be spoiled!
That's why it's called a spoiler
I hated the skultulas aswell, they weren't exactly hard to beat, but more of an annoyance. I would generally avoid them and wouldn't bother fighting them off unless I had to, same goes to anything that had an electric current running through it!
A lot of users seem to think this thread it about hardest enemy in the entire Zelda World, it's hardest enemy in Skyward Sword
Anyway, I found the Hydras pretty annoying, especially when they decide to bugger off when I have my shield ready for a shield bash lol
Armos were pretty annoying too, they always startle me when they long jump towards me lol
Technoblins, grr! I actually got my technique down for the normal bokoblins, and would wait for them to telegraph an attack before finishing them with a quick combo. That doesn't really work when there's two next to each other, since one of them will block your attack, but it's alright. Getting zapped just because the enemy blocked is irritating :p I didn't have much trouble with skulltulas, I just flipped them over and stabby stabby.
I found the Armos to be pretty hard at first because I couldn't get the timing right to stab the inside jem. But after awhile it started getting easier (although I still get killed)
The Beamos were just annoying. Like in the Sandship where three different Beamos could attack, I probably died three or four times.
I also found the Lizalfos (both normal and dark) to be a challenge. I have died countless times because I was unable to dodge the spin attacks in time. In the Earth Temple where you had to defeat Lizalfos to gain the bomb bag, I died at least twice.