There are two separate networks you are dealing with here. I'll give you an example:
IP your ISP gives you =
IP of your router =
Host System IP =
IP of your VM =
This configuration is how my virtual environment's networking looks. So you actually have two networks you would have to port forward across to get Public access to your VM. Think of it like your hypervisor (host system) IS a router for your VM.
I followed this how-to to setup my config, but you may have a more complex configuration.. it depends on what application you want to run - RDC, apache, ssh. There is more good information here. You'll have to give more detail than I would want to ask for on a public site for me to help with specifics. The principles are always the same -- make a localhost:<> connection to your physical system forward through VMware Server 2 to the VM port you want to access (22 for SSH).