I was having lock-up issues with the newest nVidia drivers on my x64 Developers Version (I'm running a GT440), so I went back to the 275 release, and it's been working perfectly since. I don't want to upgrade to the current drivers again, of course - I also used the default drivers that MS gave...
I've installed all 3 versions on VirtualBox, as well as my PC (separate partitions) and have edited the registry and changed the filename both - from what I've experienced, editing the registry does bring back the original start menu, but also leaves the 'metro ui' intact, however, with smaller...