For quite a long time I used to use native .NET application settings: http://msdn.microsoft.com/en-us/library/k4s6c3a0(v=vs.110).aspx
They are especially useful when you need to implement the user based settings.
But now I prefer to use an XML based settings. .NET XML Serialization makes it much easier and user friendly because I can have any structure including nested types as my settings.
Regards, Artem Taturevych | Snr. Developer | IC3D ANZ
IC3DSteel – New Steel Solution for SolidWorks
translationXpert – SolidWorks files language translator
Yes, I also chose the serializing classes in XML.