I don't mind laughing with people (or at people when they screw up every once in a while), but the hero in this film (who plays a really bad wannabe stunt man, just like his deceased Dad) screwed up time and again and didn't get quite how bad a stuntman he was.
In addition the guy playing "Hot Rod" was too old for the role. It needed to be played by an 18/19 year old at most, not a 30. Most 30 year olds have actually grown up and pick up on social queues when they're screwing up.
I also understand that the guy playing the title role (Andy Samberg) is from SNL (I've never caught the show). If the film is from an SNL sketch, SNL fans might like it but I doubt anyone else will.