Sharing Internet connection

My main computer is a XP and I have a cable connection. I bought a router D-link and I used it to connect another computer with W98 and my ps2 for online playing and I had no problems sharing the internet connection. It had worked fine for about a year. Now all of the sudden only the internet works on my xp computer and does not want to work for my ps2 or w98 comp. On the router were it shows if there is any activity only the cable were the XP comp is blinking. Now if I switch cables and put the W98 comp cable were the Xp comp cable was the W98 comp. will get internet but the xp or ps2 won't. I bought a new router but I stil get the same problem. I even updated the drivers on the D-link router and still nothing. I have firewall on my XP and I have disabled it to see if that was the problem but no help, also I had the firewall before it was working. I do not really care about sharing comp files I just want to share the internet connection.
Thanks.

Have you changed any settings on the router? Make sure that NAT is enabled.

When the computers cannot connect to the Internet, have they successfully obtained an IP address from the router? Can they ping the router? Could you please show me the IP config details for the XP and win 98 computer? (see the sticky at the top of this forum for details)