How to Reset a Nook
If your Nook is unresponsive or occasionally freezing, you may consider resetting your device. You can perform a soft reset that essentially remedies minor technical issues. You can perform a hard reset and return your Nook to factory condition. With a hard reset, everything saved on your Nook will be deleted. When you re-register your Nook with your Barnes and Noble account, you can sync the device with your previously stored data.
Press the Power button on your Nook and hold it for about 20 seconds, then release it. Wait for the device to power down.
Press the Power button again for about two seconds to turn on your Nook.
Confirm that any minor errors have been solved. If not, either perform the soft reset again, or perform a hard reset.
Push the Power button for about two seconds to power on the device.
Tap the white navigational arrow on the screen, then press the "Settings" icon on the navigation bar.
Tap "Device Info" from the Settings menu.
Tap "Erase & Deregister Device" on the Device Info screen.
Press the "Erase & Deregister Device" button. A pop-up window appears asking you to confirm that you want to reset your device.
Tap "Reset Nook" in the pop-up window. The device will first de-register itself, then erase all of the data stored on your Nook. The Nook will then reboot itself.