Aha!

I'm using a Lynksys BEFSR41 Version 2 router.

I'm at the network configuration screen now.

I'm allower to do Port Forward. So, if I wanted to access shared folders from another computer, I believe I could.

It says:

"Port forwarding can be used to set up public services on your network. When users from the Internet make certain requests on your router, they will be redirected to the specified IP. "

Well guys, thanks for your help!

-Drawenai