Has anyone found a solution to this yet? The problem came up for me yesterday. The day before I had no problem with right-click enqueueing. Here's the thing, I had downloaded a couple registry cleaners and ran them. Because they were both trial programs they would not "fix" the registry entries until registered. So I began fixing them manually, backing up my registry first. I fixed a little over 1000 registry keys/values but left another 1100 to do some other day. None of the issues fixed seemed to be related to mp3 files or Winamp specifically, or else I would not have touched them.
Today when I did the right-click action, all my Winamp options had disappeared. I found this forum thread and started checking things out. As much as I hated to, I restored my backed up registry, but this did not solve the missing Winamp options. So now I am not even sure if this caused the problem in the first place.
Regarding Nero or VLC causing the problem, well, I don't think either one is the cause because I have had Nero for almost two years now and VLC for about 6 months and have done nothing to them to have this Winamp issue suddenly come up. I tried uninstalling and re-installing Winamp and still no luck.
It is quite coincidental how several Winamp users have had this issue came up within the last month. Conspiracy, maybe? UFOs?
Anyways I will keep watch to see if this issue is ever resolved.