Kosher. the basic were covered by Frum Meets World really well. I, too, am amazed by the idea that most non-Jews have about what Kosher means. As someone who didn't grow up with the whole kosher food thing, it's much simpler than it looks from the outside.
The questions I hear most often vary by source. From OJ's I mostly get things like, "Does Treif (non-kosher food) taste good?" (no, it tastes awful, that's why all the Gentiles eat it, duh.) "do you miss certain foods?" (yes, like Clam Chowder and Taco Bell)
From the gentiles, it's more like "Can you eat at my house?" (not really, but thank you for asking. How about a bottle of water or a coke?) "Can't you just get a Rabbi to bless this and make it kosher?" (if only it was that easy...)
What about you? Do you have a burning question about what is or isn't kosher? No question is stupid except the one that goes unasked...