How to delete/change nVidia hotkeys?

I've noticed this too, and I've also found your thread on the NVIDIA forums.

An easy free solution, depending on what you intend to assign the hotkey to, is to use Autohotkey's function called ControlSend. Using Autohotkey you can capture the key combination and ControlSend can override it's current functionality and send it to a specific application or window, instead of NVIDIA's application.

The basic syntax would be similar to this:

^!h::
ControlSend, ahk_parent, ^!h, ahk_class CLASS_GOES_HERE
return

The Window Spy utility that comes with Autohotkey can tell you the window class if you simply hover over the window while it's running. Replace the class CLASS_GOES_HERE with the class given to you by Window Spy.

Since NVIDIA doesn't have an apparent way to unmap the key combination, overriding seems to be the easiest free solution available.

For another easy, but not free solution, there is Hotkey Commander. It is shareware (15 days free trial, $15 to buy) and allows you to add, reset, and remove hotkeys implemented by other applications:

Get Glary Utilities (which is free) or TuneUp Utilities (Awesome), Advanced SystemCare, etc. and go to the STARTUP PROGRAMS tab.

Nvidia Graphics Cards, when first installed, places a Hotkey process in Startup. It may simply say "rundll32.exe", but if you click on the properties tab, you will see the actual key is pointing to C:\Windows\system32\nvHotkey.dll,Start or something similar.

It is SAFE to delete this from your Startup Programs. It adds a few Nvidia Card-specific Hotkeys. I know this is a year old post, but if someone else sees it, I hope this helps. You can then go through the list and remove a bunch of other junk in your Startup that is probably not needed if you still have something like this DLL set to run.