I'm a little confused. After editing an image through Camera Raw 4.1, I can see a thumbnail of both the original unedited image and the new edited image in a version set. However, if I try and open the original image, I still see the new edited image. Even if I delete the new edited image from the Elements catalogue, and then open the original version, it shows the edited version. The only way I've found round this is to duplicate a file before opening it in Raw 4.1: that seems to be ludicrous.
Am I doing something really dumb?! I'm using Elements 5, Windows, the recent Raw 4.1 and Nikon NEF files.
Once ACR sees and opens a file (or maybe when PSE does so) a file named IMG_xxxx.xmp is created where xxxx is the picture file name. The .xmp file contains the data from ACR for its settings. To see the original raw file as it was before adjustments, you could click the selection box in ACR and click "camera defaults" or you could delete the .xmp file which will be re-created when the image is accessed again. The .xmp files are in the directory where the image files are kept and usually listed adjacent if your file browser is set to show file extensions.