OK kemical - I did it . I deselected Service Backup Files as you suggested , and also Windows Upgrade Log Files ( after reading it's description ) . Think that's OK? It actually went a lot quicker than I expected . Decided to do a Restart , just to play safe . Surprised to see Win Configuring Update or similar before shutdown and then similar on Startup . Reached 100% , and then stayed like that for quite some time . Saw disk light flashing , so left it . It then gave me cleaning up , which lasted even longer , and then login screen . I suspect that some of those files could only be deleted before Win 7 is up ?
Now to wait for next update .
That was a really handy bit of info on MSDOS cleanmgr . Is this stuff documented someplace or Microsoft "in-house" ?
Anyway thanks again .