Alas, readers, my knowledge of Middle-earth forsook me last night. Just as I was getting really worked up about how Gollum/Sméagol never stood a chance at the end, my dad said, "What about the ghost king?"
Ah, the men of Dunharrow. The dead men of Dunharrow, hence the whole "ghost" part. Do they not get redeemed? For those of you who are confused, you clearly haven't seen The Return of the King. Long ago, the men of Dunharrow swore an oath to come to Isildur's aid against Mordor, but when the time came for them to fulfill their promise, they did not come. Isildur cursed them, dooming them to have no rest in death. And so they died, and remained trapped in Middle-earth. That's when Aragorn comes in. As the heir of Isildur, he has the power to release them from this curse, but only if they fight alongside Gondor at the Battle of Pelennor Fields. And they do.
The oathbreakers fulfill their oath, and they are redeemed. I still wish more of the evil and enslaved races could be redeemed, but I thought I should correct myself. There is redemption in The Lord of the Rings, after all.
No hard feelings, Tolkien, right? Peace.