I think that this thread would be suited to the Helproom. However....
In answer to your question, it is possible.
I have exactly the same thing you want. My desktop runs XP pro and the laptop 98. I am on Blueyonder broadband also.
I use an Actiontec 802.11b wireless PCMCIA card for the laptop and a normal network card for the desktop. They are connected to a Netgear FM114P router (the laptop wirelessly and the desktop via a cable). That in turn is connected to the cable modem.
I chose that specific router because it had a print server built in but if that is not important then any wireless router will work.
I bought all of the gear from Dabs.com:
I hope this helps