I don't know what to make of A Knight's Tale. It stars Heath Ledger, so it has that going for it. He plays a common-born squire who pretends to be a knight so that he can participate in jousts.
The gag is, the jousts are presented as modern sporting events, with a sports rock soundtrack ("We Are the Champions", "We Will Rock You", "Takin' Care of Business"), spectators doing the wave, etc. But they don't carry through with this idea. Most of the film is a straight costume drama. It seems that the idea is to translate the concept into a modern idiom. Of course the music wouldn't be rock, but the language wouldn't be modern English either. Still, I would have preferred a movie about funny anachronisms, or a movie with fewer anachronisms. I just found it jarring.
As a straight costume drama it isn't bad, with Alan Tudyk and Mark Addy as Ledger's comic squires, and Paul Bettany as Geoffrey Chaucer, a herald and scribe with a gambling problem. But it isn't really great either.
The big question, then, is how are the jousts? With big rock themes, fancy armor and lovely horses, slo-mo collisions and shattered lances, they should be the core of the movie. I just found them to be so-so. I'm afraid that just sums it up.