Hello pgflrob, and welcome to the forums. For question 1, Ubuntu 10.04 uses 'gnome2' as its desktop environment, and while i'm sure it can be done, i haven't used gnome for a while so can't help you out.
For question 2; the file browser used in the gnome desktop is Nautilus, and i'm pretty sure you can do what you wish by opening the terminal and using the command,
As for number 3, Ubuntu is one of the distros that have decided to disable root user, and you are forced to use sudo to be granted root privileges; some people like this feature but others like my self do not. I can't help you with this one either, but i remember seeing ways on google describing how to unlock root user; which is probably what you want, which after doing so, you should be able to use the command,
, type your root password and then it'll remain root until you type exit, or you just close the terminal.