Window Problem

have OS X 1.5.8 on my Mini.
Any open OSX windows rapidly shrink into the upper left hand corner, then bounce open again, constantly repeating. Do use a wire mouse.

Problem may be my wired Mac keyboard. My problem comes & goes, so I was going to transfer everything to my MacBook Pro. When I tried to create a file name, the Left Shift-W wouldn't work, but the Right Shift-W works. Cleaned the keyboard, still have the issue. Easier to just get another. Hope that solves the problem.

Got new keyboard today. That definitely was the problem. Thank goodness. Trying to keep the Mini going until Lion and the next upgrade of Mini's. Thanks for all that looked at the problem. Realized that the problem was so weird, that maybe nobody had ever heard of it. Story of my life