re: Reset Types & Uses
^ Whatever type of hard reset you do, don't restore from backup. That will restore all your software to the previous state, possibly reintroduce the problem in the process, and with that undo exactly what you were trying to achieve in the first place (start from a fresh slate).
If the random reboots occur frequently, you could alternatively opt to restore from backup anyway. Then just realize that if the issue persists, you'd still have to do another hard reset to ensure it's not a software problem.