advantages vs disadvantages?
What is actually new?
The best system microsoft had was windows 3.1 with Dos 6.22 with a 5.0 supplement!
At that time the OS was what it was supposed to be; which was to allow your hardware to interact with other hardware. Input devices to processing devices to storage devices to output device. They finally put out the xbox which they should use as their new OS. The later would bring a better following.