The passwords are independent of eachother. All users can have the same password and it shouldn't affect the machine.
Why is it you can't access root? What happens when you try?
The way to get around this is to boot Linux into singleuser mode. This will give you root permissions. Use the 'passwd' command to change the root password and you should be OK. To boot single user mode for:
a) LILOtype 'linux single' at the LILO prompt. If you have the graphical screen, press crtl+x to get to the boot prompt.
b) GRUB[/] At the GRUB boot screen, select the Linux with the version of the kernel that you wish to boot and type e to enable you to edit. From here, you will be presented with a list of items in the configuration file for the title you just selected. Next, select the line that starts with kernel and type e to edit the line. Go to the end of the line and type single as a separate word (press the [Spacebar] and then type single). Next, press [Enter] to exit edit mode. Back at the GRUB screen, type b to boot into single user mode.
Then type passwd to issue a new password.
Note that in single-user mode, you PC will boot to runlevel 1. Your local filesystems will be mounted, but your network will not be activated. You will have a usable system maintenance shell.
Another way is to use a bootable CD, such as knoppix. You can boot up with it, mount the linux partition, and edit the Shadow file to remove the root password. Then you can make a new one. I think it's /etc/Shadow. Use pico or vi to do this. You have to delete the characters after the word 'Password' to reset the password.
Good Luck. Post back if you still have trouble.
