To answer your question about router software, it normally relates to onboard software that is on the router itself. This is normally accessed by typing in the routers IP address and you then specify the settings in that.
See
HERE for an explanation as to what a router is and how it differs from a Switch.
As for reccomended routers, check out
HERE for a list of reccomended routers that will work with an NTL connection.
I reccomend ones by Linksys.