Suppress Video Ouput?

[biolizard89]

Is there any way for an ASM hack to make the video output of the game stop updating, while the rest of the game continues to run as normal?  E.g. I'd like to make it so if I hold a button, the video output doesn't update until I release the button, but the game keeps running, pad data keeps working, etc.  All I can think of is hooking the VBlank or GXDraw routines, but I really have no clue how to do that or what I would do once I've hooked them.  Furthermore, I assume the VBlank routine contains lots of code other than the graphics stuff; when I was coding for GBA a few years ago I would stick timer and pad code into the VBlank, and I don't want that code to be skipped.

Any suggestions or help would be appreciated.