These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Cliché Storm: There's an eclipse, an apocalyptic showdown, ancient sealed powers, an ordinary high school student, a Chosen One prophecy, and a tragically dead parent figure. But eclipse, ordinary high school student, and prophecy aside, this isn't the fault of the adaptation; just about all of the rest is present in the original anime and manga. Then again, the anime didn't attempt to squeeze "all of the rest" in at once.
Ensemble Darkhorse: General agreement among fans is that the best qualities of the film (other than Brian Tyler's epic score) are the delightfully hamtastic Piccolo (as played by James Marsters) and Roshi (as played by Chow Yun-Fat).
Germans Love David Hasselhoff: Naturally, it did well in Asia (outside of Japan where it lost to Yatterman), going number one early on before dropping off. It should be noted that it was number one for several weeks at Asian box offices, and while the reception was mixed it is still rather popular and well-liked outside the US.
Ham and Cheese: James Marsters as Piccolo and Chow Yun-Fat as Roshi were awesome casting choices.
Narm: The line "The first rule is... there are no rules." is absolutely laughable for some because it didn't convey any sense on what is said.
Never Live It Down: The movie itself earned a reputation by Dragonball fans and generally, the anime and manga fandom as a terrible Hollywood live-action adaption of a very popular anime franchise. Because of this, the fandom would remain skeptic on Hollywood's attempt on adapting manga and anime into the big screen. The reception of Edge of Tomorrow might have change this view but it is still not enough to change the fandom's perception.
So Bad, It's Good: Most of the reactions were negative, even from those who never saw the animated series. That said, it can be enjoyable. A small minority think it was a decent film in its own right, to the point it could be considered an okay film had it not had the Dragonball name. And as stated above, alot of people in Asia love the film.
Special Effect Failure: See what Goku's head collided with when grandpa Gohan knocked him off. Sure, he was falling pretty fast, but melons shouldn't be THAT soft, should they? Also in the previous scene, one of Goku's kicks didn't even touch his granpda. Force Kick in effect? The 2 consecutive failures can be seen in one video.
In Goku's case, in the series, he was known for having a rather hard head.
There's also that one scene with Goku and Piccolo in a Ki blast struggle... that ends with Goku shooting himself towards Piccolo with no propulsion whatsoever and in the same Kamehameha firing pose.
There's also a bad case of Styrofoam Rocks towards the end of the movie. You'll know it when you see it.
And let's not get started with either the obviously fake ape suit substituting for Oozaru or the wretched CG used throughout.
They Just Didn't Care: Though, at least one person cared. According to the script-writer, his original script was a much more faithful adaptation of the original, complete with Pilaf and his gang, Oolong, Pu'ar, the Nimbus, etc. Unfortunately, the script was changed a lot once it was out of his hands. To the point where he felt the need to issue the above-linked apology for the final product.