I'd be very grateful for help in connecting my usb adapter running on a Windows 98 computer to a Truemobile 2300 wireless router running successfully via ethernet modem on my windows xp

1) I have successfully installed my router via ethernet modem onto the Dell computer (XP).
2) I have installed a Belkin usb adapter onto my old computer (Windows 98)
3) However, the Truemobile installation cd does not work with Windows 98.  It tells me to type in http://my.router to access the web-based configuration tool.
4) However, that only brings up a 'This page cannot be displayed' message.

So my problem is: how can I get beyond no 4, above?

The Belkin adapter recognises the router and is at 100% signal strength. However, it cannot link on to it (ping it?).  Curiously, it does link to a signal (of about 30%) coming from somewhere nearby (a neighbour?) which is of limited use.  
How I can access the web-based configuration tool? Or is it a matter of changing the ip addresses on my windows 98 computer?
If so, how do I do that?

would be really grateful for advice.    - PVR