Oh, great topic!
Personally, I give the top spot to Mask of the Lunar Eclipse. The move to an over-the-shoulder perspective and the "touch" mechanic where you held a button (and your nerve) to reach out and open door, pull back curtains, pick up items from dark corners, etc where both fantastic additions to the series, and the atmosphere was phenomenal.
Still one of my favourite Wii games, it's a crime that it didn't get a global release back in 2008, though at least its now finally playable in the West thanks to the current gen remaster.









