Original poster here. Happy to say my issue has been resolved.

As others have noted, the issue is due to the gesture sensors. An updated gesture driver can solve the issue, but requires sending the unit to Netgear's San Jose, CA office for the install. Tech support was very helpful in resolving my issue. They reached out to me; I never submitted a ticket.Tech support was responsive to my questions, and followed up with me frequently.

The process was:

Try a factory reset. This did not solve my issue.
Disable gesture sensors. This can only be done remotely, and only by Netgear. Once the gesture sensors were disabled, my issue with images changing and random menus popping up stopped completely. I waited a week to make sure.
With the issue confirmed as due to the gesture sensors, send the unit to San Jose CA for updated drive install. Netgear provided a free Fed Ex shipping label.

This should have been the end of the story. But for some reason, when I got my unit back the updated driver did not solve my problems. The problem persisted until I again requested the sensors be disabled.

Netgear then offered to send me a second unit, but unfortunately, it had the same problems, and I returned it. It came from their warehouse, and did not have the updated driver.

Netgear then sent me a third unit, directly from their San Jose office with the updated drivers already installed. That unit has worked perfectly, without issue. The gesture sensors are enabled and working properly, and the image does not change when "freeze image" is turned on. After testing the 3rd unit for a week, I returned my original (defective) unit to San Jose using the pre-paid shipping label Netgear provided.

For anyone experiencing this issue, I recommend submitting a support ticket and it can be resolved. At a minimum, you can request the gesture sensors are remotely disabled which makes the problem stop (albeit with the loss of the gestures). I worked with Rose in Netgear support.

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