I adored this series when it aired on HBO, and was a far cry from the disastrous live action movie. This movie, along with the following two seasons, tell you far more about Spawn's plight than the movie, but is more practical than reading the comics. If you're a casual fan, and can appreciate the more REALISTIC content (extreme violence, sex, language, mature themes), then this is worth the time. I was a road warrior when this was on HBO, and saw most of the episodes in dingy motel rooms across the country. It was usually the highlight of my week. It's not anime, but if you like anime's penchant for violence, sex and examining the darker side of human existance, you'll like this.
One thing to be said for the series, it is one of the best English voice acted animation series I have seen. The animation isn't perfect, but it is very well done. I believe it was done by the same Korean studio that did Aeon Flux. The characters are well done, too. My favorites are two detectives that are trying to figure out why all these bodies keep showing up all over town. My biggest problem with the series is that HBO dropped it after 3 years, and it doesn't really come to a satisfying ending. I keep hoping beyond hope there is going to be Spawn 4. So if you're not squeemish about blood and sex, and you appreciate a lot of action and good artwork, and don't mind a highly dark plot, check the Spawn series out.