One Good Knight by Mercedes Lackey is just a fun read -- not particularly deep, but great escapism. It's about Princess Andromeda, heir to a small kingdom. When a dragon starts ravaging the landscape, Andromeda is one of the sacrificial virgins offered to appease it. A Champion appears at the last moment, rescuing Andromeda and chasing away the dragon. Andromeda and the Champion set off to find the dragon's lair . . . but what they find when they get there is not exactly what they were expecting.
My boss recommended this to me, saying it reminded her of Tamora Pierce, and I agree. Also, this book is technically the second in a series, but it stands on its own just fine.
(Reviewed from a copy borrowed through my library system.)