Most of the time if you go to the "general" and the "about" you'll be able to tell.
Yes, you can put music on a jailbroken iPod Touch.
The fourth generation iPod Touch has not been made yet, and there are several other iPods with a fourth generation, so specific information of the iPod is needed to know whether it can be jailbroken or not.
you cant
I don't now a other way to get cydia of but the only way I know how to take cydia of is to restore your iPod touch
Yes, the iPod Touch with the 2.0 software can be jailbroken.
yes restore it
I guess
Once jailbroken, the iPod Touch's one year warranty is void.
it is battery
Not without erasing the jailbreak.
No...
A jailbroken iPod Touch is certainly legal. However, the act of getting every app in the App Store for free (the ones that require payment) is illegal.