Octorok: Simply classic. Although the enemy itself is not difficult to defeat (excluding the boss in Minish Cap), it is merely the idea that this monster has been involved in some form through-out the series, until Twilight Princess. To me, to sum up the Zelda series with the name of one enemy: it'd be the octorok.
ChuChu: While this enemy again, is not too difficult to defeat - it is one enemy that sums up the more recent games in the series. They, like the octorok, are an enemy that stick with me and are one of the first enemies I can remember defeating while in game.
1. Redeads: Who weren’t scared of these as a kid?
2. Lynels: toughest enemy in the overworld. How can you say no to that?
3. Stalfos: a classic.
4. Iron knuckle (AoL): Very fun to kill
5.Three of a kind: ermm… peculiar at the least.
Darknuts and Iron Knuckles. I love the sword clashes against those guys. I wish they would make more challenging enemies like that.
The Darknut is WAY better than Iron knuckles though, because they can actually make a tough fight. I think they should make Darknuts like Dark Link in OoT, with counterattacks and the ability to parry your stabs.
Of course I have to give a shout out to the Octorocs for the obvious reason of being in the series from the beginning. But besides that i'll list a few others that I liked, I didn't necessarily list all the games they are in, just which ones I liked best from whichever game.
Patra (LoZ) - Just a fun enemy to fight with the swirling outer ring that would move in and out.
Rope (LoZ) - Who didn't go to Dungeon 2 just to get some rupees from these guys.
Cucco's (OoT) - Not much of an enemy, but hilarity ensues once they start attacking you.
Lizalfo (OoT) - I really don't know why but these guys were fun, I guess it would have to be the way they walk and jump at you that makes me laugh.
Bokoblin (TP) - It made me laugh how idiotic these guys are, you could walk right behind them without them knowing and then they would get all excited and make a little noise when they finally spot you.
My favorite enemies would have to be Ganon in your sword duel thing with him in TP, Mirror Link in OoT, and Octoroks just because they're such a classic enemy. Been around since game 1. Plus if you say doctor octorok, it sounds funny.
Doctoroctorok...doctotorok...doctorok...Doctor octorok. actually does sound funny. my favorites:
!. ball and chain soldier in MC
2. Darknuts in all games
3. whole chuchu gang in MC: green chuchu, red chuchu, blue electric chuchu, spiky chuchu, rock head chuchu, giant green chuchu and giant electric blue chuchu.
4. all bulblins in TP
5. Zora warriors in PH