As with most projects he's in, Crispin Glover was the best part. His mastery at making his own personal creepiness hugely sympathetic is just about the only acting that crawls its way past the shiny CGI of the film. It's too bad we didn't get to spend more time with him outside the mead hall. They could have easily stolen a little material from John Gardner's novel about Grendel.
What I really didn't like was just the video game-looking, motion capture animation. I'm still not crazy about this no-man's land between hand-drawn animation and live action, and at my age that's not likely to change. (I do like stuff like Bug's Life and The Incredibles though, because they're reminiscent of the old Rankin-Bass holiday specials.) I probably would preferred the more atmospheric, low budget, live action version the writers originally had in mind before Robert Zemeckis came along with all his money and computers.