Normally, the registry and the jack assignments should only be touched in specific situations. Because the System Mixer apparently is not recording has nothing to do with the jack assignments. Thus you should put them back to the original configuration.
Exactly what do you mean about the System Mixer not recording? What program are you using to record? What are you trying to record? Streaming Audio from the Internet? A microphone input? A Line In Input? Or is it that you do not have any audio at all, which would be more than just a system mixer problem.
Have you reinstalled your PC or motherboard vendor's
drivers for Vista/Win 7? (You also need to fill in the "My System Specs").
We can't really help you without more info.