When I try to draw with my pen, it sometimes registers my pen press as a right click and brings up a circular menu for selecting tools, particularly if I press and only move in a small area. This is is very disruptive and I am trying to figure out how to assign this menu to a different key or disable it. Is this possible?
You can change the shortcut for the popup palette in Canvas Input Settings–> Show Popup Widget.
edit: I totally read the question wrong. A case of not enough coffee before replying.
This sounds like long-press → right-click and that’s a Windows thing, assuming that you’re using Windows. Are you using Windows as your operating system?
You could disable the action in the Popup Palette settings but you’d still get the right-click in other places for context menus. It would be better and more convenient to stop Windows from doing it.
This topic covers the problem, as experienced by another user, and gives a link to an explanation of how to find the Windows controls for it:
Pad wrongly assumes I'm long pressing
is your pen/tablet xp pen ? I have one and the wrong registered pen input is a know issue from xp pen.