how do i bring my iphone back to normal?

[Jin]

hey guy! i really need seriouse help! my Iphone is 3GS and it's MC model and its 3.1.3
yesterday i jailbroke my phone by using sprit. I really need to know how to unjailbreak mine just in case i need warrenty. can you please tell me how to restore my phone. Last time when i tried it, Itunes said error code 1602,1604 stuff like that and my phone was in recovery mode and never showed up Apple logo. Last time my uncle fixed but now he moved far away so i need your help.

Can you please tell me the easiest way to recover my phone to normal status? (without any error code plz)!!! thank you!

[KellyGe]

In order to 'Vanilla' / unJailbreak an iPhone you must Restore it in iTunes then, perform an "Erase All Content and Settings" then, setup as 'New iPhone’ in iTunes.
Residual jailbreak files will be visible to the Genius Bar if you ONLY 'Restore.'
Restore it to factory setting then sync it with your computer and all apps will come back.

To Restore iPhone using the latest version of iTunes.
•Connect iPhone.
•When it appears in the Source list, click on Restore in the Summary tab.

To Erase All Content and Settings:
•On iPhone, Tap Settings > General > Reset > Erase All Contents and Settings
Note: This will delete all media and data. All settings will be reset as well.