Caveat: I don't have a Bamboo, I've got a Tablet PC but what you're describing sounds like the right click press-and-hold action which you can disable/tweak as follows:
(if you're in category mode)
Go to the Control Panel, 'Hardware and Sound' and then 'Change tablet pen settings'
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(if you're in icon mode)
or 'Pen and Touch'
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Once inside, you'll see this dialog, and you want to change the settings on the press and hold action.
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If you need to use the registry to alter this setting (Editing the Default Profile for example), it can be found in a DWORD key named TouchMode_hold, located in
HKCU\Software\Microsoft\Wisp\Tablet
Setting this value to 0 disables the behaviour.
Also don't forget to restart graphic editor after changing this setting. I had issue with gimp which after changing of settings was still causing a problem without showing up right click menu but still showing circle as it usually do on right click. – Igor B – 2019-05-21T23:27:25.840