That's just a thin piece of veneer over particle board. All you can really do is paint over it. Its not gonna look like wood unless you do some kinda faux finish. Also depending on what the veneer is finished with it might be hard to get paint to stick unless you get the right kind. Sanding it and restaining it isn't an option since it's not evan 1/16" thick. Bleach isn't gonna do anything at all.

I would just clean it real good and and easiest would be to spray it with whatever paint color you want.