We have three computers in our house, and each has a very distinct purpose/use so it's not cut and dry.
For gaming (partner) it the desktop in the office, for surfing/school work it's my notebook computer, for movies/TV its our Home Theatre PC (HTPC).
For the one used the most, probably the HTPC as we have all 450 of our movies stored on it so they can be played anywhere in our home, it holds all of our files (and is connected to our cloud back-up), acts as our DVR, NetFlix controller and TV tuner to watch what little regular TV we do.