You will want to connect the PC to the Galil via it's own network. Meaning, that you really don't want a whole lot of other computers on the same network. If you already have an Ethernet card in the PC and it's connected to say the internet or an internal network, you really need to install another Ethernet card to talk only to the Galil. This way, other network traffic will never interfere with the communication to the Galil.
Choose an intranet number range such as 192.168.2.0 This is a class C network (netmask of 255.255.255.0) that can contain 254 hosts. You will only need 2 host addresses. One for the PC
For the PC, set the IP address to 192.168.2.1, netmask 255.255.255.0, no default gateway, no DNS server. The default gateway is not needed as you will not be routing packets to any other network. DNS is not needed as you can address the Galil using it's IP address, no names required.
For the Galil, set the IP address to 192.168.2.2 and nothing else is required for it.
Steve