Xubuntu can’t set up custom network settings via /etc/network/interfaces file
To fix remove network-manager
sudo apt-get remove network-manager wicd -y
and set up your settings into 'interfaces' file
sudo vi /etc/network/interfaces
auto lo
iface lo inet loopback
iface eth0 inet static
address 10.0.0.137
netmask 255.255.255.0
gateway 10.0.0.2
auto eth0
Don't forget about /etc/resolv.conf… Read the rest