I would definitely check that IDE cable. I had the same problem and the cable was bad (although unlikely if your system recognizes both drives). Sounds to me like you need to completely uninstall Nero, clean the registry and reinstall Nero. As stated above, I believe SUI is right on the money here!
Noli Nothis Permittere Te Terere!!
EVGA 680i, Dual EVGA 8800GT'S (650/950), 4 gigs OCZ DDR2 1066, Intel Q9450 at 3.8 Ghz, Koolance Water Cooled, Dual Plextor16x DL DVD+/-RW. Dual WD 250gb 16mb Cache Sata 3.0. 3DMark06 score = 19,168.