When Billy Mitchell is describing an analogy of top WWI fighter aces, he claims the top French ace shot down 24 enemy planes. In reality the top French pilot (René Fonck) shot down 75 enemy planes, He also claims the Red Baron shot down 87 enemy planes, when he only had 80 confirmed kills.
The Donkey Kong cabinet that Steve Wiebe installs in his garage is a combo Donkey Kong/Donkey Kong Jr. cabinet, however the markings on the cabinet are those of a stand-alone Donkey Kong Jr. cabinet. Wiebe specially purchases and installs the "brains" (PCB) of the combo game into his Donkey Kong Jr. cabinet in the course of the movie.
In the scene in which Steve's son Derek is crying and shouting, the "Donkey Kong" sounds heard don't match the action shown on-screen.