Its not as hard as you think (Score 1)

As long as the cable isn't hooked to anything behind the walls, its not hard to upgrade the wiring. If you can get to the attic, I say run the wires straight up, then over to whatever central location you have. Use cat5 now, and label both sides so you know what wire goes where. Also, don't tie them together until they are out side the wall. That way, if you want to upgrade your wiring later, you can tie the new wire to the old wire and pull it through very easily. Fiber is way too expensive right now comparedto cat5. I've helped a lot of guys at work wire their houses, and that is the easiest way.