Host UBUNTU 14.04 i need redirect all traffic from VirtualBox Windows guest OS in a network of TOR? How to do it correctly to prevent leaks?
You can 'torify' your ubuntu machine, and route all traffic through tor, see the wiki here for guides for that:
Or you can set up a 'Whonix' gateway, and put your windows virtual machine behind that. There is a guide for that here: https://www.whonix.org/wiki/Other_Operating_Systems#Windows-Whonix-Workstation