I have ubuntu 10.04. After installing, I added xfce as my default desktop/windows manager. Sometime over the weekend, my computer turned itself off. (I'm not sure what happened, but when I came over to use it, it was turned off. Chromium said it wasn't shut down cleanly when I started it up again). Ever since then, xfce seems to be running gnome's desktop.

Specifically, it's using gnome's desktop background, it is using the gnome right-click-on-the-desktop menu, and not letting me use the scroll wheel while pointing to the desktop to change workspaces. When I have terminal window with transparency open, it shows my xfce background images as being what is behind it, even though that isn't what is behind it.

How do I restore xfce to its former glory?