I'm using Win 8 and love it. Best aspects of 7, but they fixed things like the copying, networks more efficient, ram usage is better, drivers are better, multi-monitor support is better, and if you want to use metro, there are some nice apps. I use the music app while working, and its easier to find stuff than the old start menu in metro. If you have a touchscreen at all, it just kills the other touch OSs. All this and we're not even talking about a true beta. This may be the GOAT OS. People just got to get over this I'm on a desktop, I hate metro.................well don't use it. only reason for a desktop user to touch metro is when searching for a program. Press the windows button and start typing what you want. That simple.
As for hardware, depends on what you want. Pretty much all the laptops leaked or shown at computex were tablet convertibles or touchscreen laptops. You'd be perfectly fine with current tech, as Win 8 would be easier on the hardware and is fine with using just the desktop. If you want an entertainment machine like an HP touchsmart, they work great with metro. We use one next to the sofa to control music, videos, thumb through media center. It was ok with 7, but it has come to life with 8. As much as we like it though, I'm definitely replacing it with a touchscreen ultrabook that we can move around a bit and dock when not in use. I think when the general public gets widespread use of it on tablets people will want it.