airport frozen mac mini

Having trouble with my mac mini. As soon as I boot it up, it is sluggish. Placing the mouse over the airport symbol shows it perpetually spinning (ignores my clicks, needless to say). For now I'd be happy with being able to just turn it off (use internet on a different computer). I've tried a few other methods. Trying to open network in system preferences. Locks up. Tried opening internet connect form applications. Locks up. Tried opening airport setup assistant. Locks up. And these are annoying lock-ups: ignores my force quit requests. Even ignores reboot request, must unplug to reboot. Even if I just reboot and try to ignore the problem, the computer runs very slowly. Hard to ignore. Any way to turn the airport off? I guess I would also like to having it work again of course. But for now, just getting it turned off would be nice. Many thanks for any suggestions.