Did you use it with a kinect? It was designed for use with a kinect from what I can tell. Were you using it as a home entertainment hub? I upgraded last weekend, and yes a lot of stuff broke. It's either that or you run viruses from the eighties. I enjoy then new interface, and am excited that all the content from my xbox will be available on my pc, which is a lot easier to hack than an xbox.
go back, load all your movies, turn on netflix, amazon prime, buy a kinect and play with the development kit. Hook it up to a 42" screen. Until you have done that, then you have not tried windows 8.