I need to install multiple virtual images (6) of Windows 2003 Server each with say 4 Processors & 2GB RAM.
Running 6 VM's configured this way will severely degrade performance on both the Host and the Guest is running all at the same time. Unless you have a absolute need to have 4 CPUs assigned to a Guest the use one or two at most if running several at a time.
As far as Networking goes you need to read Chapter 5 "Configuring Network Connections" in Using VMware Workstation (PDF) so as to have a better understanding of the VMware Virtual Network Infrastructure and then if using Bridged you'll need to disable automatic bridging on VMnet0 in the Virtual Network Editor and assign a specific Host network Adapter and add VMnet2 set to the other specific Host network Adapter. The in each VM's Network Adapter's Settings assign VMnet0 and VMnet2 respectively
Otherwise if using NAT, only one VMnet can be NATed however you can use a combo of NAT and Host-only on a VM or use two Host-only VMnets. Although if the VM's need Host LAN or Internet Connectivity then you do not want to use two Host-only VMnets. Again assigning the appropriate VMnets in each VM's Network Adapter's Settings.
If you need or want to use the specific IP Addresses then you'll need to modify the default IP Addresses for the target VMnets.