Version: (using KDE 4.2.90) Installed from: Ubuntu Packages Often there are "little glitches" that cause KDE settings to "go bad" or need a reset. Usually the advice given on Linux mailing lists is to move ~/.kde to a different name and to start KDE with fresh settings. It would be nice if KDE had a "safe mode" where one could start KDE with the default settings (KDE would effectively ignore ~/.kde) and could then enable them one by one to see what breaks. This would also save users who don't know what to go back and recover from their old ~/.kde directory: Kmail emails and such seem like a popular place to lose data! I will CC this bug to various mailing list threads over the next few weeks to demonstrate usage scenarios.
I don't know if this really makes sense. We should just fix the bugs causing you to want it. :)