You can reboot a frozen iPod Touch using a combination of buttons. If your iPod is not working properly, reset it to factory settings using the Settings app or iTunes.
Steps
Method 1 of 3: How to reset a frozen iPod Touch

Step 1. Press and hold the Sleep / Wake button
It is located on the top of the iPod and is used to turn on / off the screen.

Step 2. Press and hold the Home button
This large button is located below the screen.

Step 3. Hold both buttons until the Apple logo appears on the screen

Step 4. Wait for the iPod to restart
Method 2 of 3: How to Reset iPod Touch Settings

Step 1. Tap the Settings app icon

Step 2. Click "General"

Step 3. Tap "Reset"
Scroll down the main settings page to find this option.

Step 4. Click "Erase Content and Settings"

Step 5. Enter passwords
Enter your lock screen password first, and then enter your passcode (if set).

Step 6. Click Erase> Erase
This will confirm your actions.

Step 7. Enter your Apple ID password

Step 8. Wait for the iPod Touch to restart
A progress bar will appear below the Apple logo. The process itself will take a few minutes.

Step 9. Set up your iPod
When the device restarts, set it up.

Step 10. Choose whether to restore a backup or set up your device as new
When you select your language and wireless network, you will be prompted to restore data from iCloud, iTunes, or set up your device as new. Remember to create a backup beforehand in order to restore it after a factory reset.

Step 11. Wait for the applications to be installed
If you restore a backup, the applications will be reinstalled. It may take some time, but you can use the applications already installed during the installation process.
Method 3 of 3: How to Reset iPod Touch Using iTunes

Step 1. Connect iPod Touch to your computer

Step 2. Launch iTunes

Step 3. Click on the iPod-shaped icon in the iTunes window

Step 4. Click "Restore iPod"

Step 5. Click "Check" if prompted

Step 6. Click "Copy" if you want to create a backup
You can restore it when the device settings are reset.

Step 7. Click "Restore" to confirm your actions
The process of restoring the factory settings will start.

Step 8. Set up your iPod
Do this when the reset process is complete.

Step 9. Click "Restore from iTunes" if you have created a backup
The screen displays the available iTunes backups. Click on the desired backup.
It may take about 10 minutes to restore the backup

Step 10. Wait for the content to sync
When you restore a backup from iTunes, the content will be automatically synced. It will take some time, depending on the amount of content.