I can still remember as a 4 year-old being completely obsessed with the Batman character. And I loved the movie. To put it simply, Batman was my hero. Of course this isn't the case anymore but I still think that "Batman" is a great film.
One of the most striking things about "Batman" is the set design by Anton Furst, which is very Gothic and bleak looking (during the outdoor scenes there is no sun whatsoever). The Gotham City that looked like any other in the TV series is transformed into dark, slimy crime pit in which good is basically nonexistent. Tim Burton gives the film some good direction, keeping things tight and interesting. He executed the action scenes nicely as well. Aside from the impressive set design and direction, the movie is also well acted. Michael Keaton played the role of Batman very well, giving Batman a powerful presence and a sort of everyman personality (which is even a bit off-the-wall) when he's Bruce Wayne. Jack Nicholson, meanwhile, was excellent as the Joker. He hams things up a lot, which makes sense since the character of Joker is supposed to be a complete, smart-mouthed maniac. I did notice a few problems with this movie though. The story, for the most part, focuses too much on the Joker, which is silly. I mean, isn't the movie called "Batman"? The plot is bit shallow as well, which probably explains why I found it a bit difficult to pin point exactly the Joker wants to do with Gotham City. The love story was bit weak as well. While Kim Basinger did good job as Vicki Vale, she and Keaton didn't develop a lot of chemistry to make their pairing believable.
If you can ignore some minor problems, "Batman" stands as pretty good comic book adaptation. If you like superhero films, then this one is certainly worthy being included in your collection.