CDFS is the compact disk file system, which is how files are stored on a CD. If a CD image is stored as an iso file, that will also appear as CDFS. The extra disk drive you see is probably a drive that is storing an iso file. Any chance that what you think is a wifi dongle is actually a thumb drive (they can look similar)? As to why the device is recognized in Win 7 but not Win 8, I don't have any ideas there.