Ernest Scared Stupid (1991) starring Jim Varney / From IMDb: Ernest P. Worrell inadvertently releases an evil troll from his imprisonment. That's the start of the end for the world, but Ernest will do his bumbling best to avert disaster.
Here's Part 1 on YouTube: http://www.youtube.com/watch?v=hFjHrEwjNUI
From Wikipedia: After escaping the troll, Ernest looks over the legend of the troll and sees that trolls can be destroyed with something called M-I- -K. The audience knows that it means milk ("a mother's care"), but Ernest thinks that the answer is Bulgarian miak. http://en.wikipedia.org/wiki/Ernest_Scared_Stupid
I love this goofy little movie and have watched it at least 50 times. I'm not ashamed to say that it makes me laugh every time. I LOVE Barkley the Jack Russell Terrier as Rimshot. Barkley had quite a film career. That's him in "The Mask" with Jim Carrey.