It’s not possible to right click on the Desktop and changing the background by using System->Preference->Appearance would not help either.
As I learned later from a new Hollandish friend, nautilus failed to start and therefore the Desktop cannot start proberly. Now, I don’t know any better, all I know is as soon as I start nautilus back up using terminal, the Desktop appears like magic.
So the solution was simple Restart Nautilus. In fact, restarting nautilus can solve a lot of problem when something does not display correctly.
I finally gave up on PCman File Manager and decided to stick with nautilus after all.
Anyway, that’s it!