If you don't have an encrypted home directory (something you would have enabled during installation specifically), you can recover your password even if you don't recall the root password either. See here: viewtopic.php?f=90&t=110928&p=621487#p621487
xxloligamerxx wrote:i cant format the computer because i have important files..
Hard disks and other devices can and do fail unexpectedly, and fatally. Please make regular backups of important files! Also consider disasters that could occur in your home and to protect against theft, or water, electrical, or fire damage, store a backup off-site.