Creating a light, attractive desktop environment on a new low-end laptop using Openbox in Ubuntu is simple and offers you most of the features you need for everyday computing without much of the load that comes with GNOME or KDE.
Despite the myth that Linux runs on anything, Ubuntu often doesn't perform well on $500 laptop hardware out of the box. Opening the main menu can take several seconds. Running a system update can bog down the system, and the GNOME icons and menus clearly weren't designed for low resolutions and 15.4-inch screens. Enabling Compiz desktop effects may result in errors, grindingly slow performance, or even a blank screen until you pull the power and reboot.