Prior to Win8 and server equivalents, the background process "explorer" acted as the Window Manager (I also believe some libs were shared among IE, the FM (Windows Explorer) and some other stuff). So I figured that as long the FM is not active, explorer.exe is still the WM. I would not know how to identify the display server etc. Sorry, I suck too much to be of better assistance XD.
P.S.: Hey, do you know that awkward moment when Win lets you know Explorer needs to be restarted because it kicked the bucket? In such situations the taskbar etc. be gone too because they need to be, say, restarted). So I was onto something there, in terms of me not being full of sh**