You really shouldn't be logging in (via SSH or whatnot) with the root account directly anyway, unless you have real reason to. However, if you can get an xterm on the 770 and can do "sudo su -" to become root, you can then just change your password there using either the command "passwd root" or "passwd user" to change your root and user passwords respectively.

You could write just "passwd" to change it but that changes for the logged in user, which could be either "user" or "root" depending on whether or not you "sudo su -":ed first, so better to spell it out which user you are trying to change the password for.