Dream Linux is a unique distribution in the fact that few other distributions ship with more than one window manager. Most choose just one window manager and stick with it. If you want something different, you'll need to install it yourself. In Dream Linux, the first thing you're greeted with when you boot the live cd is the choice between booting into Gnome, or XFCE. Overall though, the way both are setup, it's more a question of preference than anything, since there's very little visual difference between the two.