DSL, yes.
My good computer is on WinXP and my slower is on 2k.
The router is a Netgear RP614. The DSL modem is right next to the phone jack, I am running an ethernet cable to the router which is on top of my fast PC. From the router I am using slots 3 and 4 to go to my computers. The second computer is only about 6 feet away.