Philip Pullman. Just read Dark Materials and a couple of the detective ones and now I'm on the lookout for more of his stuff. Nothing too heavy, just good, interesting story telling with some lively quirks. Page turners.
Would absolutely not recommend any of the Harry Potter books. I know they are children's books but I wouldn't give them to a child to read in case they got put off forever.
Harry Potter has to be one of the very, very few instances where the films are infinitely better than the books. It is no wonder that she got turned down by lots of publishers. The stories themselves are not bad, if generic but her writing is just awful, awful, awful.