How to delete Mac OS X 10.2 preferences?
These folders store preferences:
Hard Disk -> Library -> Preferences
Hard Disk -> System -> Library -> Preferences
Hard Disk -> users -> username -> Library -> Preferences.
If you delete one of the preferences of a running program
you may run into problems. You should be very careful. Get Info on the Preferences folder storing your preference file and note the Ownership and Permissions originally and then change Ownership and Permissions to allow (Me) to edit the folder. Then you can change info on the preference .plist file itself and drag it to the trash, and change back the Ownership and Permissions of that Preference folder to what it was originally. You may need to restart the Mac and repair permissions using
Applications -> Utilities -> Disk Utility, using its First Aid tab before you can trash the file and get things back to normal again.