Chair is about 6'-8'. Nobody notices the computer noise. It may be audible when the room is quiet but with anything playing even at a low volume. HTPC is in a full ATX case. The NAS is actually right by the HTPC but I built an actively cooled case for it.
FWIW I find playing rips the best way to watch stuff. The process of ripping a disc during the day might take a few minutes but I'd rather spend those few minutes when I'm not trying to sit down and enjoy a movie. If I have to play a disc because it won't rip I use a dedicated player which is easy and reliable even if there are FBI warnings.