Using DISKPART and the "VDISK MERGE" option, is it possible to specify that you want to keep the existing child/parent disks and do a merge into a new vhd file? That is; I still want to keep my original child/parent disks. As far as I can tell from the resources I've found, the only option is to select a differencing vdisk and merge it with it's parent(s).
Take a copy of the parent and child first, do the merge, and then rename the copies back.
Cant find any other useful information on that sorry, my suggestion: boot the machine with with some WinPE or Dos from cd/floppy and use norton ghost or altiris to clone the disk that the machine sees to an other VHD drive or file share location.
I guess linux and some "dd" magic will do to.