Typically /home/username is owned by username and its group is either "users" or username, depending on the distro. Not sure about what Ubuntu uses. Permission on these are 700.
The files and directories under these have the same ownership, but will more typically be 755.
You can changes these recursively using chmod and chown using the -R option.
When you say you backed up using -avz, did you restore using -avz also? -a should be sufficient to maintain ownership and permissions.
Try something like
chown -R username:users /home/username
chmod -R 755 /home/username
chmod 700 /home/username
as root (or using sudo).
Edit - what did you do to lose sudo access? You may need to boot a live CD or similar to edit /etc/sudoers.
Last edited by billymayday; 11-10-2008 at 03:24 PM.