I think the 911 thing is dependent on whether you have home phone connected to an old fashioned wired land line or you have a home phone line via your cable company. But you are so right - things change so rapidly with technology, my info could be out of date.
I keep the home phone for filling out forms for various stuff we must have these days. The home phone screens the calls from solicitors who are sold our contact info, so I can just delete them.
Granted that is not the greatest reason to keep the darn thing...