Check out the photos on portorleans.org. I personally don't think they are too "princessy". I think that's why they are called Royal Rooms and not Princess Rooms so it doesn't isolate boys. The bedspreads are a dark color and there's a few princess touches throughout the room, but nothing over the top.
All of the Royal Rooms are in the Oak Manor and Parterre Place mansion buildings. There's a bridge across the river to the main building in between the two buildings, but I think Oak Manor is in a better location if you'll be walking to the main pool at all. Parterre Place is the furthest mansion, closest to POFQ. It can be a hike if you are on the end closest to POFQ. You can request either building.