I think I just found out the answer why some computers shut down slowly this is all down to one shell called explorer.exe

but when I started to use AstonShell (www.astonshell.com) the shut down speed has really improve a lot as well as the start-up speed. AstonShell is much more stable then the explorer.exe itself. it even take up less ram and cpu usage then explorer.exe. AstonShell has fancy animated icons the style of the shell it just a bit like mac os x.

AstonShell is better then explorer.exe is better then every aspect of it.
I would really recomments to anyone. AstonShell has plug-in support.

try it out (30 days trial $29.99 to register)

http://www.astonshell.com