I would absolutely watch a Red Green film.
They made one and, boy, was it terrible. It didn't capture what was so funny about the series at all, which I suppose isn't really shocking.
Red Green was always a series of short vignettes with only the faintest of a narrative backbone. It was also best in 20 minute bursts.
Moreover, the narrative backbone was always the weakest part of the sereis, and when they tried to stretch it out into a movie, it wasn't nearly strong enough to hold things together (it didn't help that the show's 20 minutes were also stretched into the movie's 90 minutes).