DLP is indeed Sleeping Beauty --- "La Belle est Dormant" and I'm sure I'm saying that wrong in French, despite completing Rosetta Stone.
You can't walk through the castle in DLP but you can go upstairs and see stained glass windows with scenes from Sleeping Beauty and you can go into the cellar and meet Maleificent.....a "real" fire breathing dragon complete with cave, mist and fire. I think my son was 8 before he'd go in there....
You cannot eat in the DLP castle either; Cinderalla's Auberge is next door, complete with glass coach outside.