This is one of many reasons that I never do upgrades. I always do fresh installs. It can be a lot of work but at least you don't have as many surprises.
Try booting the first installation CD. You should be able to get into the system repair section and have it set the root password on your hard drive. I don't recall off hand but you may have to select to perform an installation, then select your language, then it will ask you if you want to repair an existing installation.
Last edited by stress_junkie; 06-24-2007 at 08:17 PM.