I do not want to affect you, but have you gone crazy?
Why would someone like to have their SystemRoot as DocumentRoot?
Everyone would have Access to all Files on your System.
People could easy open a cmd Box and format your disk etc. pp
But anyways, you should change C: to C:/ then it "should" work.
But don't say we didn't warn you!
Designers don't do things because they like to do them but because they can't do it another way. The /htdocs folder can be named anything you want but there is a reason for having some folders not reachable from the /htdocs folder... Those folders are not reachable from a web site. Only if someone can physically log in through the command line. Then someone could just cd .. to get to the lower folders. But if you put the htdocs folder in the lower place, there is no place to hide what you need to hide. That is a passwords folder, some programs and vital data!