Since you are asking here I'm assuming your question is with regards to just the telcom/network wiring.
If you are opening up the walls I recommend running CAT 6 ethernet cables to every room from wherever your services come in. Make sure you use cables that are rated for in-wall installation. Run 2 cables to the living room.
Yes. Consider running 2 Cat6 ethernet cables to shared rooms such as Living room, and a single Cat6 to each bedroom. Terminate them in a location where you can add router and switches, and ensure there is an electrical outlet to power the necessary components.