In both Caputure One LE and Canonís Digital Photo Professional, I can view RAW files (read straight from the Flash Card) in the image editing window, but I cannot alter them in any way.
That's by design. Editing a RAW file is like altering a film negative; something no sane photographer does except in extremely unusual circumstances. If you can't open a RAW file to convert it, that's something else entirely. RAW converters don't generally support opening/editing converted files. Have you tried ACR to see if it opens the files? You may have simply had a disk malfunction and have a whole folder full of corrupted files.