The Jailbroken iPod has Cydia, which "unlocks" or makes your IPod capable of more tasks than a regular IPod.
Yes. .... Just restore on iTunes
Yes, just sync like normal
No. You will not see any performance difference.
You have to go to jailbreakme.com from your ipod
Restoring an iPod should reinstate the warranty to a jailbroken iPod, unless a problem occurs during restoration, then the warranty isn't in effect since you are trying to restore a jailbroken iPod.
Yes, you can put music on a jailbroken iPod Touch.
Yes, but it will erase everything on the iPod, including things available only to jailbroken iDevices, such as Cydia, Winterboard, etc. You can then put all NON-jailbroken media back on the iPod by using a backup file of the iPod which is saved on iTunes.
You get sydia
if you mean the line then that is normal but if you have jailbroken it then that might be the cause
yes if your warranty is still here and your ipod's not jailbroken.
yes
No, they shouldn't.