Not "either", but both. 
Do it right the first time. Figure out your physical layout. Wired connections are better IMO than wireless, but they involve draping wires all around or drilling holes in the wall - options which may not be appealing or possible. See if your layout can include some limited wiring from your primary router to a distant point, with secondary wired distribution from that distant point. In other words, run one wire upstairs and put a new switched hub up there. Now you can service several wired connections from that point without needing every one of them to have its own wire going all the way back to the primary point. If there are yet other areas that cannot be serviced by wire or would be more convenient with wireless, get the wireless cards for those systems. Now you have the best of both worlds.
dw