Restoring Photoshop Back to Default
1. First, hold down all three Ctrl+Alt+Shift buttons
2. Now "while keeping those button held," simply right mouse click and press 'Open' Photoshop
3. You should get a prompt asking if you would like to "delete the Photoshop settings file", Click 'yes'
It is a simple fix that allows you to reset all of your Photoshopsettings and preferences back to factory default.
From what I know it works with
CS2
CS3
CS4
CS5
(From my knowledge that is)