As the topic title suggests, something has gone slightly wrong during my install of Ubuntu 5.10. Question is, can I correct it without having to re-install?

su to root functions as any other distro; I am asked for my root password, and upon successfully entering it, I am logged in as root.

sudo, while installed and executable ALWAYS fails to recognize my root password.

Speaking of passwords - considering what I had heard about Ubuntu - and continue to hear about it - I find it a bit odd that I was asked to specify both root and user passwords during the install.

for sudo you should have to enter your USER password, not the root password. And in the event that doesn't work, edit the sudoer file by typing visudo as root. Then add a line at the bottom:

yourusername ALL=(ALL) ALL

Of course, to use sudo correctly, you should only give yourself permission to do certain things, but that's way more complex than just letting you use sudo for everything...

Aha! The user pws for sudo - how very devious...

As nothing happened when I tried to launch apps such as Synaptic using sudo, I tried editing the sudoers file as you suggested. Now Synaptic and the like work - but I am never asked for a password!

--EDIT: Sorry, I was too quick on that last issue. A reboot sorted it out.

What probably happened is that the sudo config file (somewhere) has a default time where once you insert the password, then for, say, 5 minutes you won't need to enter it again. After you haven't used sudo for 5 minutes, it'll prompt you for your password again.

Yes, I have since learned of the time limit on sudo sessions - but thanks anyway!