>IMHO, an option group in some cases is more clear and natural than a checkbox. For example, "Do you want to kill the dog?" with the choices "yes" and "no". What's the prompt for checkbox? "Kill dog?" ... if checked, yes?
>

If the check box is to signify that an action should be taken, it's usually inconjunction with another action (assuming you are looking at a dialog whose function it is to ask questions about the job). If the yes/no question is the only thing to be asked, you would normally not be looking at a dialog, but a messagebox with yes/no buttons. In the case where "Kill the dog" is one of several other inquiries, I think that "Kill the dog" as a caption for the checkbox is perfectly suitable.

>I guess I'm thinking grammatically. A checkbox to me represents a boolean flag, an indirect question, while putting a yes/no checkbox denotes direct action and the natural control for a firect question. The difference being (former to latter) .. "oh, btw, I want to kill the dog" as opposed to "Yes! Kill the dog!"


Well, a check box is never supposed to _do_ anything on its own except for enable/disable other UI elements (same goes for optionsbuttons, BTW). If the action is to be taken when the choice is made, you need to be using a messagebox.