Creepshow is a near-perfect anthology film. The weakest story in this film collection is possibly They're Creeping Up On You and that one's only bad because it feels like a weak Tales from the Crypt episode. However, the best story is easily The Crate.
The effects are top-notch in this film, the stand out of course being the beast from The Crate. This movie features some of Savini's best work. I love the comic book esque panels featured throughout the movie and it definitely captured the look and feel of EC Comics better than the best episodes of Tales from the Crypt.
I don't know how else to convince you that Creepshow is worth checking out. It's a film written by Stephen King, directed by the father of modern zombie movies, has effects by Tom Savini, and features a great cast. Seriously, if you haven't seen Creepshow before, you're seriously missing out.