Yes and no. If you sync it your iPod will remain jailbroken. If you update it to say 4.1 it will un-jailbreak your iPod. Then you will need to re-jailbreak it.
You hit the reset button.
Easy and simple. You have itunes and then connect to computer. Open itunes and select your ipod. Near the bottom right corner there should be a button sync. Sync it, When syncing make sure you don't skip the backup step. Then click update ipod. It will take a while and then it would usually say open from backup. Select yes or ok. After this sync ipod again the same way and walah done!!!
No. If you sync your iPod it wont delete your apps. But if you click "Restore" while the iPod is plugged in, then it will restore you iPod to how it was when you bought it (no apps, no contacts, etc.) and then update it to the newest version of software.
To 'unjailbreak' an iPod Touch, you have to do a system restore, which is available in the iPod Touch home menu in iTunes. This will erase all content that is on the iPod Touch, including bookmarks in Safari and contacts in the Contacts.
All you have to do is update to the latest firmware.
click update in iTunes. Side bar in right > Your ipod "whatever you named it > Summary > Update. It should pop up asking you to download and update in a dialogue box when you sync your ipod with your computer.
Yes iTunes>(iPod Touch Name)>Restore
yes if you have the playlist in itunes drag it onto your ipod.
Yes, updating the software of an iPod undoes the Jailbreak.
Yes, first sync your ipod though. Don't update to 4.3.4 or 4.3.5 yet as those have no untethered jailbreak.
All you have to do is just hit the reset button.
If you want to sync only certain songs: 1. Open Itunes 2. Plug in your Ipod 3. Go to "the name of your Ipod" tab 4. Uncheck "Automatically update music" 5. Drag music from your library to your Ipod tab. If you want all of your library music on your ipod 1. Repeat steps 1-3 2. Check "Automatically update music" 3. Click "sync"