How to tweak function hints (popup help windows)

Is there a way to disable the automatic popup of function hints in the command window and just get it on demand, with a double-tab or something? Or, less ideally, is it possible to increase the delay time before it pops up? I'm aware of how to disable them altogether, but would rather tweak how they're implemented.

Once in a while I find these little popup help windows helpful, so I'd rather not completely disable them, but I don't want them popping up when I type "plot(" and think for 2 seconds. It's more than a dislike of the popups; I'm often typing the command with a figure window I'm working on in front of most of the command window, and when the popup appears the command window moves to the front. A Windows 7 fix to stop the command window moving to the front when the popup appears would also work. I'm running R2011b.

Thanks, Steve