Well it's not like the story is being continued in the show format anymore.
And now that I think about it they could still try it later if the live action version fails miserably. A big part of DBZ for me at least was the look of it. I liked the animation style. That will be completely gone in a live action version.
One thing I hope they avoid completely is the 4 hour powerups. They could make like 10 movies if they spent the last 30 minutes of each one powering up only to hit us with "To be continued...".