If you have made changes to the registry...and performing a restore has not resolved the issue...then you may have inadvertently damaged the registry beyond repair.
If you are stating there are several programs that will not respond anymore...you may be forced to perform a clean install. That would be my suggestion.
WARNING!
However, before you even attempt a clean install...and have access to all of your important files, documents, etc., etc...I would back them up prior to performing the clean install.
I'd also wait for other techs to reply to your post...before attempting a complete reinstall of the OS.
Problems with making registry changes...and not knowing exactly what it is you are changing or removing means yo may have several problems with software that may not respond as they did before. This means you could be performing troubleshooting tasks on many programs...which, in turn, will take quite a bit of time.
Either a recovery...or re-installation of the operating system, to me...would be your best bet.