Denise0608, as someone who heavily relies on my phone, I can imagine how frustrating this may be! You mentioned you performed a factory reset on the phone, what steps did you take to complete that? How long has the rebooting and freezing been going on?
depotman51, we know the importance of ensuring that your phone is working as it should. Let's take a look at the options available for your phone. Can you please confirm the Galaxy S model of your phone? Do you recall what action you were performing when your phone froze this way? TanishaS_VZW