wwwthreads was the original name, then around 5 years ago when Infopop (now Groupee) purchased the software the name changed to UBBthreads.
Rick has always been the main developer of the software from day one and continues to this day

The software allows for both threaded and flat views and allows the user to switch on the fly between the two.
I think the software will be perfect for your requirements and is the only forum software that I know of to offer both flat and threaded views on the fly.
Enjoy
