OK thanks. Win 7 (6801) is actually very stable. Other than this and some software incompatibilities I haven't faced any problems.
I got the same problem when i rename user32.dll to user32.dll.bak. There's nothing i can do about it, not even task manager will see it and end task. I have to restart the machine to take it off my screen. Like ubuntu83 says everything seem to be in a stable state now other than some incompatible software and this bug. Hopefully MS will fix this in the next beta.