Why is it that I can buy a brand of computer that simply is not apple that has twice the power and speed and pay less than half the price?
Because you don't know anything about computers or operating systems. You can compare hardware specs all day but they do not compare across OSs. You may have bought a computer that you think has twice the power and speed but in the end its not going to be "double" the speed of the Mac.
Mind you I'm a windows tech by trade and I've set up a ton of windows systems from laptops to high end workstations to servers. I have far more windows experience then mac experience but I can tell you hands down that unless your a gamer the mac is the better buy for performance and stability.