I DID enter passwords for both root + user (regardless of how nagging the full name request is), and as soon as I rebooted, I could NOT login to the system neither through kdm, nor through tty1 console. Regardless of how I tried, I never got to enter the system KDM does display the root and user accounts, but does NOT accept passwords.
Try pushing the key to activate the numbers at the alphanumeric keys.

It happend something similar to me with a compaq notebook.

Regards