Buying a computer based upon how much space it takes rather than by what it can do is perhaps the most mindless thing I can think of.
Unless of course you don't do any real work or have any real entertainment needs.
My last purchase was primarily based upon wanting to stream blu-ray quality audio and video from my computer to my audio/video system. The video part was much easier than the audio part.
Of course all of these things come in a small or at least medium-sized form factor now.
Maybe a nice coloring book would suffice for you...