Restoring Original Settings to iPhone #1

Since my old number was ported to iPhone #2, and iPhone #1 was named "James's iPhone", I needed to change the name of iPhone #1 to my wife's name. How do you do that? The only way I could see to do that was to restore the original settings much like you do with an iPod that's giving you trouble. I crossed my fingers and punched -Restore-. It worked! I gave iPhone #1 the appropriate name and now it's just a matter of syncing some of her favorite things.