Looking at all the hubbub about the movie '300', I couldn't help but think that many people need some guidance in reading a movie review. So here is a handy set of guidelines that I use when reading movie reviews, and a few points to keep in mind.
Rule #1: Always go to the professionals. Let's face it: anybody that sees a movie and then immediately runs to the computer to post a review has had an extreme reaction. Everyone else wanders off to more interesting pursuits. And more often than not that extreme reaction was a negative one. So the flood of 'F' grades that appears on Yahoo Movies or IMDB isn't really telling you anything except that some cranks saw it (see rule 6).
Rule #2: Remember that the professionals are probably unqualified to review the movie in question. Reviewers are like everybody else, in that they have favorite kinds of movies. But the paper isn't going to have three reviewers, one for action and one for comedy and one for art house movies. They'll have just one, so the critic must pass himself off as a jack of all trades and pretend to like all kinds of movies. But people with real passion for movies, who decide to be critics, more often than not come from the Art house clique than anything else (it seems). So they're not really the best person to give an opinion on a sword-and-sandals epic or the latest gripping technological thriller.
Rule #3: Everything is a three-point scale. If a reviewer uses a five-star system, it means that 4 stars is average, 3 stars is bad, and five stars are movies that are his specialty (see rule 2). They don't actually use one or two stars (see Rule 4 for exception). This is so that they can legitimately claim that they're not hurting the business of the theaters who, after all, pay for a lot of ad space. But if a reviewer says "Worth seeing" and gives it 3 stars, what she's really telling you is "I would rather jab my eyes out with hatpins than see this atrocity again."
Rule #4: Always read one home and one away review, and adjust accordingly. Find a reviewer who should like it and a reviewer who should hate it, and see what they say. Low scores from the 'home' reviewer are especially damning. If the movie reviewer for 'Greenwich Salute to Angst' says that the newest French film exploring middle-class ennui isn't poignant enough, and gives it only 4 stars, it's probably a terrible film. Low scores from the 'away' critic are a perversely good sign; if the local critic hated the French film but loved 'Coed Car Chase 2' then that's a boost to it's score. The lower the bad rating, the better. Find a film that gets 0 stars on the 'Away' review and you might have an all-time great on your hands.
Rule #5: Remember the code of the playground. Reviewers do not like to be only one pushing a movie unless they're getting a kickback from the studio, nor do they like to badmouth critical successes. You don't get invited to the Oscars like that!
Rule #6: As usual some people are just cranks. This is particularly true for the non-professional reviews, where people delight in being negative about a movie simply because so many of the other people liked it. But the same vibe exists in the critics' world also, albeit more rarely.
Just remember that, since movies are so expensive, you might be better off waiting until it comes out on video. Of course, be sure to rent it legally, as the days of no-knock raids against video pirates cannot be far off. Happy viewing!