Apps crashing on one user only
Since Mountain Lion, OS X is also caching preferences, what I personally think is an bad idea. :) It's like "Oh we made the Library folder visible again since Lion, let's make another hurdle against over-intelligent users deleting files and configuring on their own so we do not need to support their problems and to protect us!"-idea. :) 

Back to topic. :) 

On your path to delete the dark side app preferences, did you try:

defaults delete -app &lt;YOURAPPNAME&gt;


in Terminal.app? For instance, for deleting even the cached preferences of Apple Mail, you would invoke 

defaults delete -app Mail


That resets all the preferences for Apple Mail and puts default values in the prefs file.

If you did, then try to load the default prefs you created:

defaults read -app &lt;YOURAPPNAME&gt;


BEFORE that, you could do displaying the prefs file for debugging that everything is ok:

defaults read -app &lt;YOURAPPNAME&gt;


If you see some binary trash, you can be sure the problem is there...