I'm not sure if this is the correct forum category. Please move it if not.

Somehow while installing openSUSE 12.3 64bit I damaged my 12.2 installation on a separate partition. Now when I boot into 12.2, open a console and invoke "su" i get

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:~> su
Password: 
su: cannot set groups: Operation not permitted
...and "sudo"

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> sudo ls
sudo: effective uid is not 0, is sudo installed setuid root?
As far as I can see the ownership of all directories at the / level has been changed from root:root to a user1:users, user1 being myself. This may have happened when I was trying to copy my home directory to the newly installed 12.3. Is there any solution to this, like "chown -R / root:root" or do I have to re-install my 12.2?

I would normally just switch to using 12.3 except that a vital piece of emulator software does not work under 12.3 causing a total lock-up.

Thanks for any assistance.