If you are kicking off an X-windows GUI you will need an X server, such as Reflection or Exceed. I don't know if there is a free one out there.
VNC gives you access to the X desktop, but only at the expense of true multi-session functionality. It's great if all you want is to export one desktop over a decent speed network, but you will not be able to do basic things like cut & paste between desktops.
I'd recommend Exceed, but only since it is the only X server that I've used more than once.
Once you have the X-server all set up & you want to start the GUI, you will need to define which display it should start up on.
So;
$ export DISPLAY=XXX.XXX.XXX.XXX:0.0
$ ./program &
where XXX.XXX.XXX.XXX is the IP that you have given your Windoze machine (you will have given your 98 box an IP already).
But you probably know that already, yes ? Ian
"IF" is not a word it's a way of life