My kids are older, and they were scared around every corner by the creepy wax figures. I know that might seem obvious, but it even creeped me out. The only reason we went was because the signs on the outside made me think it was the Gangster Museum. They are drawing on the fact that you think it's the good one and set the bait with their signage. Yes they have a few exhibits that you can read. One neat secret passage type thing, but seriously the room that exhibit is in is pretty much the totality of their "gangster museum"- a cold and nasty room with copies of newspapers up on the wall during the time Al Capone and other mobsters were making the news.
Basically, it's an unkempt building with scary inaccurate (for the most part) wax figures.