Using Nautilus with root permission

gksudo gedit /usr/share/applications/Nautilus-root.desktop

Insert those lines into the file:

[Desktop Entry]
Name=File Browser (Root)
Comment=Browse the filesystem with the file manager
Exec=gksudo "nautilus --browser %U"
Icon=file-manager
Terminal=false
Type=Application
Categories=Application;System;

Save file. Go to: Applications -> System Tools -> File Browser (Root)

Or:
apt-get install nautilus-gksu

After Logout, Login: Right-click on a folder and "open as administrator"