It will mess up you backup data and all the apps/music/video/photos will not be on your itouch. you would have to restore it again to have everything on it. so it is best to wait.
Yes, restoring your iPod will take off the jailbreak, and you will have to jailbreak it again.
yes, by restoring it.
it breaks.
A while.
...
Nothing.
Un-jailbreaking your iPod Touch means that iTunes must recognize your iPod. Without the recognition, you cannot Restore the iPod (Restoring it 'un-jailbreaks' it). Your warranty is void since you made an unauthorized modification to the iPod (jailbreaking it voids the warranty). The best you can do to 'un-jailbreak' it is to take it to an Apple Genius to have it restored from there.
(iPod Touch)Try restoring it by first plugging it to your cumputer and itunes then just pressing the both the home and the button on top of the ipod for 10 seconds, then let go of the button on top while still holding the home button for 5 seconds, then on the screen you should see a button that says RESTORE...press that button... it should take a minute or so.. just wait..enentually it will be restored and youll be using you ipod touch again......
Take it back to the store you bought it from, with the reciept and show the people at the store what happens when you try and use the iPod
Then just sync your iPod to iTunes if it is on your computer. Select the app and sync your iPod (be prepared if it is going to back-up your iPod, which may take a while depending on the content on your iPod).
You hook your Ipod touch back into your computer. Get it to sync all of your apps back on. This may take a while
WARNING: Jailbreak voids warranty. It is not illegal though. Connect the iPod to your computer. Then Jo to spiritjb.com and click on your computer type. Download then your iPod will reboot. THis may take a minute so be patient. When it reboots go to Cydia where you can do things to your iPod. Winterboard will be downloaded with it and that's where you can check and uncheck the things you get from Cydia All set! You can still sync regularly with iTunes. Dejailbreak by connecting to iTunes and restoring.