Gremlins (1984)

The friendliest door into the genre, though it bites harder than its reputation. Joe Dante sets it in a snowy, Capra-style small town and lets the gremlins behave like drunk party crashers, trashing a bar and taking over the local movie theater. The kitchen fight, where a mother takes them on with a blender and a microwave, is both hilarious and nasty. It was one of the two 1984 films whose violence under a PG rating pushed Hollywood to create PG-13, which tells you how far the scares go.