The movie is a continuation of the drama, and probably would not be as interesting if you haven't been introduced to the characters and plot already. It is a show about delinquents so eye candy was definitely not on the list of casting requirements. It is actually based on a manga so they really tried to match the look of the actors with the manga. Some of the guys clean up okay in other dramas, but it is not an ikemen drama by any means. I would say that the drama is targeted more toward guys than girls, though there were a lot of female fans too.
If you like gokusen, or underdog stories then you probably would like it. In Japan the movie was more successful than hana yori dango, though the drama didn't do as well.
Rookies is one of those dramas that people are either fanatically obsessed with or don't like at all, so it really depends on your type.
