virtualbox.org

Have: windows host with 2 ubuntu servers installed.
Should: make ubuntos see each other over ssh, make each ubuntu able to see outer world.

Are there some graphic examples of the network structure in this case somewhere, couse I can't imagine what is going on under the VBox GUI tabs.

The simplest way would be to set both servers to use bridged mode networking. They would then behave like other machines on the network. If you have a DHCP server they would get their network config from there. You would not need ssh for them to see each other - they could communicate directly on the network.