Characters are chased by zombies, but the monsters are so slow-moving, awkward, and poorly acted that most viewers will find these scenes funny rather than scary.
Much of the action takes place in a dark and spooky cemetery, but the cemetery set is so obviously fake and cheaply built that only young children are likely to be frightened; most older children will find these scenes to be comical.
Flying saucers are attacked by the military, but these scenes consist of stock footage of military bombardment poorly edited together with cheap, incompetent, and obviously phony saucer effects. Young children will probably find these scenes merely confusing, while most older kids will find them laughable.
Unlike older children, younger children may be mildly scared by some of it, but any older child will easily handle it, and in fact, probably think it hilarious.
There is some violence between characters, some gun shots, etc. Some scenes will probably disturb very young children.