Tired of chasing old men in masks, Daphne and Fred go off to start a successful TV series, Velma opens a mystery bookstore and Scooby and Shaggy works as customs officers at an airport. However when Fred decides that the next episode of their show should be about real ghosts, the gang get back together to travel across the deep south. After many `men in masks' they arrive in New Orleans to be invited to a house haunted by a dead pirates and an island full of zombies. However the gang discover that everything is not quite as it's seems on the island.
The nineties film version of the animated Scooby Doo are quite different from the original series. Instead of being cheesy, they are knowingly cheesy and contain a lot more jokes aimed at themselves for adults. While it is not quite as adult orientated as the Simpsons for example, it is still pretty amusing. Daphne and Fred both being slightly jealous of the other having opposite-sex interest is one example of this that worked quite well.
Also the film's go harder for scares from their ghosts, I'm not saying it's scary but it has a lot more action than the series! The zombie have real menace and are not just comedy characters. The voice work is good considering it is not the original cast by and large. Mark Hamil is probably the biggest name on the list and does OK but all the cast do well even if some of them are really doing impressions instead of performances!
Overall this will please kids but will also be enjoyable for adults who do enjoy Scooby. The wit is a little more than just pratfalls and there are some nice self-depreciating touches that are funny. The zombies and all are quite effective and the film is enjoyable. Don't expect art it does what it does and does it quite well.