Ubuntu – Access User Desktop Files While Using Root

Create a shortcut to your favourite file manager (Konqueror, Dolphin or whatever) on your desktop. Right click on it, and click "Properties". On the "Application" tab, click "Special settings", and check the "Run as different user" check box (the exact phrases may be different, because I'm not using English KDE). At least it is how it is done in KDE 4, but on KDE 3 it is very similar. Or you can simply write "kdesu" before the command name.

Open the file manager with this shortcut, and do the copying from here. Be warned, though, that any application you run from this file manager will be run as root.

If you want to access a folder under another users home directory instead of using ~ you need to use ~username. So I would do something like ~zoredache/Desktop. You could also simply use the full path. Typically on a Linux system the home directories are under /home, so you could use cd /home/zoredache/Desktop.

If you cannot access your home directory while logged in as root, then that indicates that you may be try to access a filesystem that was mounted with fuse. As a security measure, by default, fuse will setup restrictions to prevent any else from accessing the filesystem except the user that mounted it.