Unfortunately I don't think it is possible to get information about the movie from the fanart which is displayed.
What would be possible is hiding the menu after some amount of time.
Pressing a key would show it again.
EDIT: it is possible to transform the home screen in a picture slideshow, but I'm not sure if I should do that.
The fact that the slideshow screensaver doesn't work is a Plex issue which will probably get fixed soon.
Then the skin slideshow would be of no use anymore...
As far as I can tell, the Plex Slideshow still is not fixed. Mine just dims. Making the menu disappear would be a great alternative. ReFocus is the only skin that I like and care to use.