Yes, just restore (or upgrade if a newer version is available) in iTunes.
Hope I helped! :)
You can get an untethered jailbreak with absinthe.
iOS 5.1 untethered jailbreak
no they are working on one
Yes, if you update it to iOS 5.1.1, there is an untethered jailbreak out.
Tethered means that you have to "just boot" your jailbreak every time you reboot your device. Untethered means that you dont have to do that
Yes it is, but it will be a tethered jailbreak as there is still no untethered jb out there
No. It is just to soon for the devs to get an untethered jailbreak for iOS 6. Plus iOS 6 isn't available to the public just yet.
yes you can you use green poison rc6 for untethered jailbreak.
restore and re jailbreak
unfortnately there is no ios 5.1 jailbreak at the moment but it is coming soon. Yet there is a tethered jailbreak for ios 5.1.
You can jailbreak it semi-tethered but not untethered at the moment. search on Redmond Pie for a tutorial
Well it can't be done without shsh which needs a jailbreak to do it. But besides jailbreaking doesn't hurt your iPod and the only reason you would need to Downgrade is if the jailbreak isn't untethered but so far almOst ever firmware has an untethered jailbreak. Good luck~Jake