Do you know, the operating system for operating a computer is much more than the graphic environment. Many operating systems already separate the shell from the operating system. What's more, the shell is something that can not be done or even replaced.
GeoShell is precisely that - it's a simple, faster, and replaced with a Windows graphic shell for light one. Changes in the modified section are notable: task bar, start menu, system tray, etc.
One of the highest grossel's benefits on the original Windows shell, beyond the scope of reducing resources, is the ability to add modules similar to Linux's GNOME panel, though it still requires some polishing
If you want to try Windows shell options or free your system resources, GeoShell may be very useful.