I would suggest a complete reset and update for you.
Open Settings > System > Reset and choose "reset and update." This ought to sort out any problems you're having.
If the Settings app crashes, and you're not able to perform these steps then you get the ATV into recovery mode by unplugging the power and plugging it back in rapidly 3-6 times. Unplug the power cord, wait 5 seconds and plug is back in. Wait 5 seconds and unplug it. Repeat this until you see the "recovery mode" notice on your screen.