Well, I know I'm not in the swap, but sharing some of the love. :-)
Character I think I most resemble: Susan Sto Helit - I'm usually calm, collected, logical, but open to the idea that we adults don't always know what's *really* going on.
Anti me would likely be Rincewind. I love him, but I refuse to live in constant fear.
Favorite Character and book.... I think this would be impossible. I have so many I love for such different reasons, Vimes, Vetinari, Granny Weatherwax and Nanny Ogg, Tiffany Aching, the Wee Free Men, The Chancellor, Cheery, The Luggage, DEATH! The list could go on and on. As for the book "Good Omens" (I own 5+ copies of this book, just in case I meet someone who's never read it so I can give it to them), "Small Gods", "Equal Rites", "Going Postal", "Raising Steam", "THUD!", again, the list can go on and on.
This man and his writings totally bring out my Geek. I could talk about the worlds and characters he's created for hours and not be tired of the discussion. I also can't tell you just how many times in college I would be sick to death of reading, couldn't stand the sight of another book, but I'd still pick up the latest Discworld novel I had gotten my hands on and read until the wee hours of the morning, only to have to drag myself to class the next day as though I had been out partying all night. Never once did I regret staying up to read the book though.