Hi James,
You might visit the informix web site and download their windows driver. Once you have the driver installed on your windows box, just configure it with the info you need to make the connection. You should be able to connect to the informix database without the need for samba. Samba would only be usefull if you wanted to have windows based databases, like foxpro dbf or dbc, live on the RISC 6000 system, but be available within a window network just like it would work if the foxpro DBF or DBC were on a 2K server.
You could develop a VFP7 app to run the reports. It would involve fetching data from the RISC 6000 into a VFP7 cursor. Once you have the cursor, your home free.
I have developed an example app of using VFP 7 as a front end to a postgres backend server. It might give you some ideas. It can be downloaded at:
https://www.smvfp.com