My parents claim that they don't like Mexican food, though my mom has changed her view since she had some of the real stuff on a conference trip to Acapulco (IJCAI 2003) that I took her along on. I personally haven't met a cuisine I didn't like, though there are some very strange Asian dishes that I am not sure I want to try: take rats and water cockroaches, for example, which are Cantonese delicacy. Actually, I might try rat, but I'm squicked by dog meat, like most Americans.
I've always heard bad things about British food, but some of the pub meals that my folks and I had in Edinburgh (IJCAI 2005) included fish and chips, bangers and mash, etc. and they weren't bad at all.
Is there anything you've tried but don't want to have again? Anything you refuse to try even once?