Open ports on Linksys Router

[k s d]

Hi all. I want to open some ports on my Linksys Wireless-G router.
Below is a snipit from the Linksys help regarding port forwarding:

   When users send this type of request to your network via the Internet, 
the Router will forward those
   requests to the appropriate PC. Any PC whose port is being forwarded must 
have its DHCP client
   function disabled and must have a new static IP address assigned to it 
because its IP address may
   change when using the DHCP function.

I do have my network settings set to "Configure: Using DHCP". After reading 
above, I see that I probably have it set wrong. If I configure manually, 
what is enatailed with assigning a custom IP address with my G4? I also have 
a PC running XP wirelessly from the router. What do I need to do there? I 
know these may may seem like broad questions, but I'm not even sure what to 
ask - Sorry, I really don't know much about this stuff. If the info I need 
is something I could figure out by reading a couple of links, they would be 
welcomed also.

TIA,
Kevin

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