Well can't really say much for terrible cuase I thought were fun as hell.
But worst games I love that put hours into that got bad rating were
One Piece: Unlimited Adventure - Over 100 hours ~ 67 rating on metacritic
WiiSports - uknown # hours but big ~ 76 metacritic
So looks like One Piece is Review wise my worst game. But have over 100 hours on my save, and close to favorite game on Wii. Probably cause HUGE One Piece fan. Hoping the Unlimited Cruise come stateside.
And for my vote of game don't know why i play cause its kind of dumb/crappy yet addicting is Swords and Sandals 3