Well, mine are for taste preferences, not service problems.
I would avoid Akersaus for everything but the Storybook Princess Breakfast... that was great!
I would also avoid Biergarten, Sommerfest, Tangerine Cafe and Restaurant Marrakesh.
Nine Dragons doesn't do anything for me, not because of any experience, but because I can get good Chinese food at home.
We have enjoyed Tempura Kiku, Matsu Ma Lounge, Le Cellier, San Angel Inn (lunch), and Yorkshire Fish House.