For your home, it depends upon what you want to do with the computer. First decide what programs you want to run and then decide what is best to run them.
For the a average person a laptop is sufficient. You can add monitor and keyboard if you wish.
But, and it's a big but, if you want to do something like post processing of photos you will want a large monitor, colour calibrated, large hard drives, solid state boot hard drive, possibly dual monitors, graphics video card. This is easier in a desktop unit.
Longevity, they are similar before processor and OS will drive you nuts.
Apple or PC, again look at what programs you want to run and what it will cost you for the hardware.
For the average person doing email and Web surging a five year old computer will be fine if it has the drivers you need. For all others think of what you will be doing. That is why there is such a variety out there.
For my main computer I use a tower with good graphics card, ssd, dual hdd, dual monitors for serious work, multiple USB 3 ports. However, 80% of the time, I use a seven inch Android tablet that is over three years old.
What may work for one will not necessarily be good for someone else.