I loved the Pern books enough to reread the first six of them over and over. But few of the ones she has done since, hold up to that standard - I think she's become so popular that editors can't make her revise them properly.
I love Lois McMaster Bujold. The Vorkosigan series is great, and is available free at
http://baencd.thefifthimperium.com/2...CD/CryoburnCD/. I'm also a fan of _The Curse of Chalion_ and _Paladin of Souls_. I love how the protagonists crawl out of the pit of despair, and into glorious redemption. Ista, especially. In one of the Vorkosigan books, there's a woman who says she doesn't want to get married because for women that's the end of the story - the only thing that married women ever do is give birth to the hero and die young. Bujold seems to have created Ista to follow up that thought; she's a 40 year old widow who runs away and becomes the hero of her own story.
Like others here I love _Pride and Prejudice_ and have read it many times.
I recently read a YA book that I think will end up on my reread pile, it's called _Special Topics In Calamity Physics_ by Marisha Pessl. It's a mystery story and I won't give any spoilers, I'll just say that when I got to the end, I had to go read it again because once I knew the ending I wanted to see all the clues go by again.