Do you mean should you boot into recovery & do a factory reset ? If that's what you mean, yes. Also, sticker on phone chassis under the battery, what does it say ?
If it's important enough to cause you grief if it's lost, back it up. No excuses
Trolling for thanks is lame
Does Samsung's auto-brightness implementation crap drive you to self-harm ? A solution !
Failure to search is the leading cause of male impotence on XDA
If you don't know how to recover if things go wrong, what are you doing flashing custom roms ?