Most of the personal preferences are defined in src\GN4AddIns\TedSystemAddIn\TedOptions.vb, while some are defined in src\GN4AddIns\ShellSystemAddIn\Shell.vb.
In the Visual Studio, open the GN4 solution src\GN4AddIns\GN4AddInsExpress.sln, and then search the entire solution for <XmlAttribute()> Public to get the list of all preferences.
Preferences by main tab
Articles, Collections, Contacts, Editions, Pages, Planning, Publishing, Reports, Shell, Start, Tracking, Trash can.