LW Pro: Can't use Preferences!!

Although I'm now using LW Pro Beta 4.1.7, this problem has existed for me through at least 5 versions so it must be a corrupt file on my machine.
When I bring up Prefs I get the "Spinning Beachball of Death" and can't use either prefs or LW and must "Force Quit".
I haven't wanted to delete a .plist file since I wasn't sure what I would lose.

Any ideas out there??

Thanks,

John