sorry....i've been eating turkey
hmmm. sounds like you have quite a little pickle here...
first thing is this: the linksys ip and netmask, etc is for the router only....your router will assign a new address to the computer....something in the way of the 192.168.xxx.xxx
it is essential that you let this happen
now, the first step is to be able to FIND the wireless network from your computer, then we will work on ip address settings.
if the setup program is disappearing when you start it, then that means it is crashing. Windows XP should have it's own drivers though, so it should not be a problem
so, we should at this point have your cable modem hooked into the router (in the WAN port) and one of your computers (win98??) hooked into the router and working properly.
so....the problem now is the windows XP one, which connects wirelessly to the internet
let me know if i have all of this right so far, and we will look further