I, personally, am in favor of the LMGTFY response. When I see “dumb” questions (and by “dumb” I mean easily answered with a quick visit to Google or Wiki), I want to get them answered as soon as possible to move them along and get them off the page.
If it only takes me a minute or two to Google something for another poster, I might put in the couple minutes to “clear the land” for “better” questions. If they have further questions or if their question is more complex than they let on, they can continue the thread asking more questions. If not, I’ve answered the question and that thread can fall off the face of the board.