Originally Posted by
Delfuego
Pre-wire CAT6. Move your network gear downstairs as a pseudo network-room DMARC if possible. Buy good office grade network gear (don't skimp) not residential gear. Upgrade your ISP bandwidth and get a failover ISP if yours goes down often. Same dance we do for small offices. If you get frequent power outages, get UPS batteries. If your expected to be "always on", your gear needs to be too.
I wouldn't worry about sound and video too much, everyone has kids/dogs/etc at home and are pretty forgiving. I however don't do presentations or video conferencing if I can avoid it.
With better network gear, you can control kids internet access, availability, bandwidth and have content filtering too.
Good luck!