Photoshop CS4 Redraw Problem

I have a strange problem that just arose yesterday, running 11.0.1, up to date Bridge and Photoshop.
What happens is, when I have an image open, and do any adjustments (curves, actions), the action will complete, but the image will not redraw until I either resize the window or apply a paintbrush to it. It's not a latency issue, it just never happens.
Also, the menus on top are all out of whack. If I select one drop-down, such as filters, then move my mouse to another drop-down, only the first drop-down stays active (for example, if I click Filters and mouse over to Select, nothing will change).
I've re-installed, even deleted all the configuration and any traces of Adobe and the problem still exists and is extremely frustrating.
I would appreciate any help, short of a format, to fix this problem.
OS X 10.4.11
2 Ghz Core 2 Duo
4GB 667 DDR2 Ram
320GB Hard drive, almost half-empty
EDIT: just to clarify, I have removed all of the plugins, plugin preferences, with the exception of camera raw 5.2. all of my software and firmware is otherwise up to date and I have already tried to tweak the cache settings to no avail. this problem practically happened over night.

Wow - I wouldn't have expected a mouse driver to cause drawing problems.
You might want to contact Logitech and let them know about this...

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