Source: Photoshop Support Knowledgebase
This Technical Document provides information to find or re-create preferences files for Adobe Photoshop CS2 and Adobe ImageReady CS2.
Preferences files vary by name and location for each version, with each version storing its own preference settings in a different set of files. The technical document has a graph that shows the location for both Mac OS X and Windows.
To re-create the preferences files for Photoshop or ImageReady, start the application while holding down Ctrl+Alt+Shift (Windows) or Command+Option+Shift (Mac OS X). Then, click Yes to the message, “Delete the Adobe Photoshop Settings file?” or “Delete the Adobe ImageReady Settings file?”