if you want to be able to access the connection without having the other computer running, and this can either be a conventional wired model or a wireless type.
The principle's the same in both cases:
1. Connect the router (with its own inbuilt ADSL modem) to the phone line.
2. Install network adapters (either Ethernet or wireless) in both machines.
3. Connect the two machines to the router if you're using cable, and use one of them to configure the router, using the HTML interface that comes with the router software. If the router is of the wireless variety it will come complete with a cable so you can connect a computer to it for the configuration process.
Thereafter the router (either type) will automatically make the connection when it's booted, and either computer (or both of them) can use the broadband connection.
4. Run the networking wizard on the Windows XP machine, and select the option for it to make a floppy disk for use on the Win98 machine.
It's all pretty straightforward, and you should have no problems. You can choose external USB network adapters if you go the wireless route, and if you do that the only thing to remember is to install the adapter software before you connect it to the computer.