I wasn't disappointed, either. The first book of the series starts off a little slow, but then settles in and caught my full attention. I enjoyed the first book, I've just finished the second book - which I enjoyed even more, and now about to start the third.
If you like creepy stories and tales about magic, but a little darker than most (ie Harry Potter) then You should enjoy this.
I think anyone over the age of 12/13 won't have any difficulty with following the plot, or the bits of violence here and there.