Continuity mistake: In the scene where the boys first see the family they show a closeup of the three of them. There is an American flag sticker behind Dennis' head and a fish behind Mars' head in the back window. When they pull away from the market the stickers aren't there. (00:15:00 - 00:15:35)
Continuity mistake: Towards the end, as Willis and Pollack drive the van, Willis is seen inserting the magazines in two handguns. The next scene shows hims putting the second gun on the center console, it has no magazine in it.
Continuity mistake: In the scene in the father's house, the boy drops the DVD's face down. In the next shot, they appear face up.
Continuity mistake: About 15 minutes into the movie, Jeff is behind the red pickup truck at a red light. When the truck pulls away, there is no license plate anywhere on the bumper. Two minutes later, as the red truck is pulling out of the parking lot to follow the Escalade, the truck has a license plate on the left side of the bumper.
Continuity mistake: Right after Bruce's window gets shot out, his rear view mirror is gone, but when he sees his wife and daughter in the back of the truck, the mirror is back.
Continuity mistake: In the final scene Jeff cries after a final showdown. After a tear falls down the right side of his cheek, in the next shot the tear has completely disappeared.
Continuity mistake: In the final shootout scene, Jeff is holding a Colt 1911 style pistol, which is single action only. This means that it must be cocked prior to firing it the first time, or squeezing the trigger will have no effect. When he is holding his hands up, the hammer is cocked back like it should be, but when the camera zooms in on his face, the hammer is down. When the camera backs out again, the hammer is cocked again.
Answer: The purpose of the DVD is that the information the criminals are after is hidden in the code of the DVD. The illegal bank accounts and funds and such are all encrypted on the disk. He is also helping Jeff after he realizes that he put his life on the line for his family and saved his children.
Spaceboy_007