Matthias Saou wrote:
Naoki wrote :

  
When I try : System-->Prefs-->More Prefs-->Desktop Effects

It seems to remove all window management, I get all the applications 
from my eight workspaces on the one screen, I can no longer switch 
between workspaces (which has been reported before so I understand this 
issue) and the applications no longer have borders and are unable to be 
manipulated. 
    

I saw this on a computer where I had dri disabled in xorg.conf.
Re-enabling it and restarting X made the switch to compiz work.

Matthias

  
You sir have just solved the problem and won yourself a beer :)