I have the 4 pics 1 word and i can't open it

If 4 pics 1 word is an app

See:

iOS: Troubleshooting applications purchased from the App Store

Contact the developer/go to their support site if only one app.

Restore from backup. See:

iOS: How to back up

Restore to factory settings/new iPod

Try double tapping home button and holding the apps that show up hit the minus sign auntil all of the apps are clear