urhmmmmmmmm... i am guessing that you have a dialup modem (just because I am not certain to do with dsl/cable/t1/e1/e3/atm/oc-12/oc-3/oc-c48/adsl/isdn/dual isdn, but they might work the same way)
to share access of internet all you have to do is go to dial up networking (start/settings/dial up networkig (I thinkg or My computer/dialup in win98,95)) and right click on your connection.
go to properties. go to the far right tab and pick share internet connection and then you have to setup what ports (lazy butts like me just did all ports open to test first and make sure it worked, then I went back and did port by port what I needed).
I haven't worked with windows 2000 in a few months because I just got my linux ftp/telnet/samba thing working and it puurrrrrrssssss !! linux is GREAT! much more fun than point click point click (i am reffering to the command line, i am not a person for x windows (kde, gnome, etc).
but anyways.
email me if you don't figure it out or get it working. I have a book at home and I will type the information out that you need 🙂
later-lee