My first guess is that you do not yet have ALL of the software re-installed on the PC.
I do not know if you are aware of this, but... Nero makes a complete "suite" of video software, and it is typically called "Nero Ultra." They also then take some of the components and peddle them as separate programs, and they also sell several of these smaller separate programs to DVD writer manufacturers and also to PC manufacturers, to include as a "freebie" with the purchase of one of their units.
The "Nero Ultra" package consists of several programs (Nero burning Rom, NeroVision Express, Nero Recode, Nero Showtime, Nero Drivespeed, etc., ad nauseum.
The one program you referred to in your post -- Nero StartSmart -- is actually nothing more than a menu, of sorts, which serves as a sort of a "E-Z portal" to the other programs. It will only load up the particular programs that it actually "sees." If it does not see any of the DVD programs (such as NeroVision Express, or Nero Burning Rom), it does not display those as options.
So, check, and double-check, and determine which of the Nero programs are actually installed on your PC. Go to Control Panel, add/subtract programs, and look carefully at the list.
Here is a link to a list of the main programs that make up Nero Ultra, so you can at least go into your control panel and see how many might be installed right now on your PC.
This is further confused by the fact that Nero has also made different "packages" which have been aimed more at music files, and CD burning, and burning of data files. It sounds as if you have some of THOSE programs loaded, but that you do not have the Nero DVD software programs loaded.
The link for Nero Ultra:
Link to the MAIN programs that make up Nero Ultra
Note the descriptions, and note how some are music-oriented, and some are data oriented, and some are video-oriented.
Hope this helps,