"First, let's clear up one area of frequent confusion;
the difference between a desktop environment and a window manager.
A desktop environment typically consists of icons, windows,
toolbars, folders, wallpapers, and desktop widgets. They provide a
collection of libraries and applications made to operate cohesively
together. A desktop environment contains its own window manager,
which is responsible for the placement and appearance of windows.
"We have selected 6 of the best desktop environments that are
good candidates for older hardware. These typically run well on a
machine with a Pentium II 266MHz CPU and 128MB of RAM. All of the
desktops are released under freely distributable licenses. If your
Linux box is constantly swapping or feels sluggish in general use,
try out one of the desktops featured below. It may just save you
from discarding a perfectly good machine."