Low level preferences editing

[Guest_imported]

I'm experienced in Windows, but a beginner to Macs. In Windows, settings can be directly edited using regedit, or by editing human readable INI files used by some programs. Is there a way to directly edit preferences on a mac? Eg. How would I change the background image without using the control panel?

 

[jimbopalmer]

Resedit is a tool to alter programs and files without access to the source code. (my strong advice, never edit the origonal file) I tried to remain child-like, all I acheived was childish.