Comment 15 for bug 294104

The restore command is called in the following way from the menu:

su-to-root -X -c /usr/sbin/simple-restore-gnome

With sudo you run programms as the user you logged in with but with root privileges and with the su-to-root command you run programms as root.

It seems that some preferences of your root account are wrong or incompatible to your other user accounts.
You can try on the console:
su-to-root -c /bin/bash
set | grep LANG

to see what your root accounts language is and compare with your users account.