ReDead

ReDeads are highly annoying zombie like creatures, and leave many Zelda fans to scared to play again. They emit an ANNOYING scream and freeze Link in his tracks. While he is frozen they will hop on Link's back and do some sort of odd movement (possibly biting), and drain his health. A highly similar enemy, called a Gibdo, has appeared in many Zelda games, including Ocarina of Time and Majora's Mask.

Appearances

Ocarina of Time

ReDeads made their debut appearance in Ocarina of Time. Their appearance is similar to that of a zombie. When Link approaches a ReDead, it will "screech" at him, immobilizing him temporarily, giving them a chance to jump on his back and start eating his brains out, which by no means looks comfortable. This takes a ton of hearts away if you don't get it off fast enough. If this happens, and Link does get jumped on, you can mash buttons to try and remove it. They take alot of hits to kill, and can be quite frustrating sometimes.

If you do not want to be stunned, you could stun them instead using either Deku Nuts or the Sun's Song.

Majoras Mask

ReDeads appear once again in the sequel to Ocarina of Time, Majora's Mask, and they attack the same way. However, they will only attack Link in his Child or Zora forms. The reason for this is because, since Zora Link is so much like Adult Link, from Ocarina of Time, the animation for ReDead attacks was already done. Because the animation for an attack on Deku or Goron Link was not completed, the ReDeads would still screech, but they would not attack either of these two forms.

There are several ways you can kill a ReDead. You can stun them with Deku Nuts or spin into them while wearing the Deku Mask, preventing them from attacking you. A Goron Pound is quite effective against them, as well as Zora Link's magic power. An even simpler way, however, is to just shine light on them using the Mirror Shield, which kills them instantly.

If you wear either the Captain's Hat, the Garo's Mask, or the Gibdo Mask, they will dance around, in which case they will not attack you, no matter how much you attack them.
They usually drop quite a significant amount of Rupees when defeated, so you can use this to your advantage to stock up.
Interestingly enough, if you shoot a Gibdo with a fire arrow, they are revealed to just be ReDeads.

The Wind Waker

ReDeads in The Wind Waker are pretty much exactly like their Ocarina of Time counterparts, if a bit more annoying. They attack by screaming, which immobilizes you momentarily, giving them the perfect opportunity to jump on your back, dealing tons of damage in the process. You can kill them fairly easily, however, as just a few sword slashes will do them in. If you shoot them with the Bow, Boomerang or Hookshot, they will just creepily stare at you.
You can actually stun a ReDead with the Mirror Shield, if there is a light in the room. This does make them significantly easier to defeat.
ReDeads are found in the Earth Temple, Savage Labrynth, Miss Marie's cabana on Private Oasis and several mini dungeons around the Great Sea.

Twilight Princess

The ReDeads in Twilight Princess have many significant differences than that of previous games. For example, their size. They are much larger than a ReDead in any other Zelda game, as well as much creepier. Rather than attacking by jumping on your back, this variety screams at you, then hits you with a huge sword, dealing lots of damage in one shot. You could attempt to run up and attack them one to one, but they will probably end up screaming again. A good strategy is to use the Clawshot to get close to them, and then immediately attack them before they have a chance to attack you. Even easier, however, is to use a jump attack as Wolf Link, which just makes them a joke. Later, once you get the Ball and Chain, 2 simple hits with that will finish off these zombies.
They are found in the Arbiter's Grounds and the Cave of Ordeals.