This is one of my answer to the same problem that has been asked a few times on here."Apple says "If you cannot turn off the device using the slider, press and hold the Sleep/Wake and Home buttons at the same time. When the device turns off, release the Sleep/Wake and Home buttons." Now there is a way to erase the password but I am not sure if this would work when you are already disabled. This will not erase any data on your device. I guess you can always try and hope you have a windows computer :-) anyhow you plug in your iPod. Open My Computer (or Computer for Vista). Click on Folder options and enable to view hidden files. Next go to iPod_control and click on the folder named Device. If your iPod is locked, there will be a file _locked . Rename the file to _unlocked. Remove your iPod and it will be cleared" you can also check on here http://www.ifixit.com/Answers/View/45131... The other thing you can do, is to plug your iPod in the computer that you normal use for it and see if it can be restored that way.Good Luck.
You will need to restore it to regain functionality. This will delete all data on the iPod, including music, videos, apps, ect. Use this guide to put the device into DFU mode, then open iTunes. Select your iPod in the sidebar, and click restore. It will download the update, and restore the device to factory settings.