A man volunteers to bring his girlfriend’s son home for the holidays from his boarding school. The boy doesn’t want to visit his mom, so the man basically kidnaps the kid. Along the way they face many difficulties and their relationship eventually grows to mutual respect. The man buys a ton of fireworks during the trip to try to impress the kid & they get accidentally detonated causing a huge show. The movie is maybe 15-20 years old. The kid’s dad, who reneged on having the boy for the holidays, is a rich, arrogant asshole.
Dutch AKA Driving Me Crazy (1991).
Google: “girlfriend’s son”+movie|film+fireworks
That’s it!! Thanks so much, was driving me crazy! I had the movie on Beta, but no longer have a working beta tape player.