Locate the NVIDIA Display Driver Service, right-click it and select Stop.To disable the service tap on the Windows key, enter services.msc and hit enter.
I have not experienced any other issues doing so however.
When you do that, you won't be able to access the NVIDIA control panel anymore. You can disable both process by stopping the NVIDIA Display Driver Service.
Update: You may notice the two processes nvvsvc.exe and nvxdsync.exe running on your system even after you have only installed the modules that you needed to install using the custom installation option.
You can download the latest Nvidia drivers from the official website. I suggest - highly - that you also check the perform a clean installation option unless you have created profiles that you want to retain. I disable all features but PhysX during installation to avoid installing drivers that I do not need on my system. It checks online to find new drivers, can optimize games so that they run better on your PC, and video broadcasting options.