Eragon, the movie, created from the book by Christopher Paolini, opens today in theaters. The book, written by a home-schooled teenager to fill the gap between graduation and college, was first privately printed and sold at genre events, then picked up by Knopf in 2002 and rose to New York Times bestsellerdom. The history and plot of the book are highly derivative of the more familiar Pern series. It is also liberally seasoned with Lord of the Rings, as is most modern fantasy. The movie will fill fans of Anne McCaffrey's books with fervid hope that computer-generated effects have finally reached the point where they might film her rather more complex stories. Meanwhile, most of Eragon is unobjectionable. Opening in theaters today.