I think those two pieces would look great in white. Once you were done you would have a very ecletic looking space.

I would not paint the desk because it look pretty as is. The little end table is up to you. I agree that the entertainment center looks a bit mod for your space, but if you like it then call it eclectic and go with it. Painting other pieces white will not change the fact that the entertainment center is very mod compared to the desk, which looks more elegant and will not look modern because it is white.