Hi,
There is no such list of description for all registry entry.
Did you want to customize your scroll bar on width & height or color?
If you cant to change its width& height, edit this registry:

If you want to change its color, please be note that 'scrollbar' item allows only a width change, not color wither in Aero and Windows Classic modes. It picks up the '3D Objects' color.
Please remember to mark the replies as answers if they help.
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