I like this thread.
I'm going to have to agree with Matzilla on water chestnuts. They have the consistency of onions saturated with water, and ruin almost any meal I've ever eaten that had them in it.
Any sort of pork or ham gets to me too. It just feels like eating plastic meat. Bacon is good but most other pig meats taste awful to me.
I don't like onions, peppers, lettuce, or tomatoes either. Burgers should be meat, cheese, pickles, and a bun. That's it.