I recommend WinDirStat.
I frequently use WinDirStat to create screen shots for user documentation of open folders and their contents.
It even uses the correct icons for Windows registered file types.
All I would say is missing is an option to display the files without their icons. I can live without it personally, since I am usually pasting the image into a paint program or Visio to edit it, but it would still be a useful feature.