I, too, liked Princess Isabella. It is a surprisingly entertaining and intelligently executed little game. The voice acting is great and some of the accents remind me of characters from Babylon 5 and of old-fashioned, cold war type, eastern European spies. Most of the puzzles are quite simple; others, not at all.
The pixie is sometimes annoying, and I wished for a way to swat her. Other than that, the techniques put a pleasant spin on IHOGs. I'm thinking here of the curse removal scenes in which the castle is transformed and of the pixie's abilities.
I played this one at time when I was certain to be called away at any moment by various family and personal emergencies throughout the day but still had to be around the house. Isabella fit the bill for amusement. If this game were a wine, a connoisseur would describe it as refreshing and unpretentious.