Windows 7

[compdoc]

> The second problem is that Windows 7 notebook can't see any of my Linux
machines and that includes the Ubuntu machines.


Are you sharing anything from the Ubuntu PCs? My Windows 7 Pro system can
see any machines that have Samba shares, but not the others. 

However, it can access the others using ssh or vnc. One way to find them is
with an IP scanner, or just know their names and addresses, and how you need
to access them.