This movie is a poor adaptation of the anime that loses points for not staying true to the storyline.
The movie tries to use the original Dragonball story line of Goku meeting up with Bulma and Master Roshi and Yamcha, etc... but the story gets taken in wrong directions. For starters, Goku is supposed to be a very young boy, but the movie has him turning 18 before his adventures start. Throughout the Dragonball series, Bulma isn't much of an action hero, rather she is a comedic teenage girl that makes us laugh. The movie tries to portray her as a Tomb Raider style gun toting action star with horrible aim. The worst alteration of the story line is messing with Goku's origins (*spoiler alert* that he is Piccolo's minion reborn, rather than a Saiyin).
If this movie would have been a simple martial arts film, it would have done better. But because they tried to use the Dragonball story and then changed it in key areas, it comes up short.
Give this one a pass (or just rent it) unless you are an avid collector.