This is actually from another thread - I was responding to something TofuTheGrape was discussing.
I thought it might deserve it's own thread. Sorry if I'm wrong about that! 
PROBLEM:
Your Photoshop Beloved is acting WACKY. Things aren't behaving as you know they should. Buttons don't work and filters don't filter. Chances are your Preference files are FUBAR and need replacing.
BONUS PROBLEM: once you reset Photoshop to the factory CLEAN setting, ALL your personal tweaks and settings in the Preference Panel are also toast. You have to go and a) remember what the hell you had set which way b) actually go set them.
ONE SOLUTION IS:
0) Shut down PS and then start it up again while holding down
Alt+Ctrl+shift while photoshop is starting up
Once you've reset your Photoshop Preferences (another way is to just go find the Pref file and physically DELETE it - same effect) here is what you should do:
1) Your new "clean" version of Photoshop will now not have any of the "custom" preferences you may have previously set (eg: brush tips, memory allocation, ruler settings, etc.). So
BEFORE YOU DO ANY ACTUAL CHOPPING, go ahead and take time to set everything the way you like it. You can quickly get to the PS preferences panel by typing CMMND+K (cntrl+K for PC).
2) Once your preferences are all just the way you like it (you DID turn on the crosshair option for your brushes, didn't you?
) you then
SHUT DOWN Photoshop WITHOUT DOING ANY CHOPPING.
3a) (here is the main tricky bit)
Go find your PS Preference File!
Hint: MAC
Hint: PC (this is for CS3 - other versions will be nearby this location, but you may have to hunt it down)
3b) The file is called
Adobe Photoshop CS3 Prefs.psp The file you are looking at is a) pretty much a factory reset file b) has your PERSONAL prefs encoded. Right click (cntrl click) this file and resave it to the SAME FOLDER but RENAME IT
Adobe Photoshop CS3 Prefs.psp-COPY.
4) that's basically it - you've got a back up of your tweaked prefs in a very clean state. What you do if your Photoshop starts acting WACKY (and it will if you are really using it like it wants to be used!
) is this: a) Go back to where your PS pref file is kept, DELETE the
Adobe Photoshop CS3 Prefs.psp file. b) make ANOTHER copy of the
Adobe Photoshop CS3 Prefs.psp-COPY file, and rename ITS copy
Adobe Photoshop CS3 Prefs.psp .
5) go start up PS - this way it will be pretty much a factory restore, but you don't have to piss around setting all your persoanl preferences again (and if you are like me, you got it tricked out something FANCY! :8 )
