You are going to lose everything. The phone will be just like it was the day it came out of the box. Now if you are backing up your contacts either by saving them all as Google contacts or by using VZW backup manager you will get those right back. As far as e-mails go they will all resync with the device as you sign into the accounts they are associated with. Text messages are gone. There are programs on the market to allow you to back them up, I've never used any so I can't say how well they work, Apps will also all be deleted but if you make sure in the settings menu under privacy that back up and automatically restore are checked before you do the factory reset and then go into settings accounts and choose sync all the data will all be backed up to Google. Then after the factory reset as you are setting up the phone again be sure that automatically restore is turned on and all of your apps will start to download again. I would suggest making a list of the downloaded apps just in case so you know what you have and want back. Also this only restores the Google market apps so anything that you have downloaded from other app stores such as the amazon one will have to be re-downloaded manually