Yes, it's a movie; yes, it is an odd conglomeration of Spanish and English tossed together. It is a melding of cultures in a language format.
Our kids were raised in Spanglish due to the uniqueness of our own multicultural marriage. Dad's first language is Spanish and mine is English, although we often drift into the other language. Besides that, because both of us worked when the kids were younger, we had to have babysitters. We chose sitters that spoke Spanish, figuring that English would eventually take over here in the U.S. We lived in an agricultural area when the kids were little with a rather high hispanic population, so it worked for us.
Early on, we never taught numbers, letters of the alphabet, animal names, or any of those early words that kids typically learn in English. They were all Spanish. However, the English sentence structure stayed. Hence, Spanglish. The kids would come out with sentences like: "Look, mommy, that caballo is bonito." (...that horse is pretty). Or, screaming this one out..."eeeeeeee...the ganzos went caca on my cabeza!" (the geese pooped on my head). It was a traumatic experience for 3 year old!
After a few years, we moved over to an area that had less percentage hispanic population and it was difficult to find sitters who spoke Spanish, so the kids had more exposure to the English language. By the time the kids went to kindergarten, one of them still spoke a form of Spanglish and attended ESL classes. The younger one was fully integrated in English before attending school and never went to ESL.
Their language of choice now is full-on English, although they both can pronounce Spanish and understand much of the language; not fluently though. Daughter is now attending Spanish class in high school. The teacher suspected early on that she knew Spanish and kept trying to catch her, but never could because my daughter DOESN'T speak Spanish. She knows lots of songs in Spanish, lots of words, lots of things in Spanish that most English speaking kids don't know; but she doesn't speak Spanish. They learned a song in school, sort've a Spanish childhood nursery song, which my daughter had heard numerous times as a child and she sang it fluently the first time out. Made the teacher just a tad suspicious. I told my daughter that if that teacher had any questions or concerns, please call me at home and we will talk. Although my daughter is not a straight A student, she does get good grades in Spanish.
OK, so Spanglish is not an official language, but it is spoken by millions here. It is just another sign of how language is an ever changing, dynamic method of communication. It doesn't need to be official in order to serve the purpose of its intention.