Bad king and wizard want to stomp out all independent thought; dragon rider and his friends want their land to be prosperous and free.
Violence pushes the PG edge, with bloody injuries and faces, brief sadness following a character's murder, and wraithy figures who swoop around in darkness; battle scenes include huge armies wielding multiple weapons (spears, arrows, flames, swords, knives); battle between two flying creatures (good dragon and bad smoky dark beastie) has them biting at each other, resulting in bloody wounds; riders fall from horses; magic spell leaves victim with black spidery veins and debilitating "illness."
Mutual attraction between Arya and Eragon is established -- without much spark but with some sensual glances; Eragon's relationship with the dragon is "romantic," though it stops short of being sensual (some lines are comic, whether intentionally or not, as each declares their mutually interdependent "power").