I had a problem and found that a driver pxHelp20.sys was changed and was a size that was more than double all know sizes for this program which can be MALWARE. I researched the driver on the web, decided that it could be removed based on what some people wrote, and used sysinternals process explorer to delete it from autorun. Turned out to be a bad move - now I can't do any CD burning. How can I get this back into autorun? I've tried reinstalling Nero, Roxio and neither corrected this. I have a registry backup done before I did this but am not sure exactly how to restore this and can't seem to find a definitive answer even to exactly what importing the registry in regedit does.

From what I can see by a quick search is that that file belongs in \windows\system32\drivers There should be an autorun.inf file for the program that pxhelp.sys belongs to. You might have to edit that file.