Patti, the first thing that I would try is to restore the iPod with itunes. Make sure you use the computer that you use to sync your iPod with, otherwise you will lose your library. If that makes no difference, see if you can place your iPod into disk mode by following the Apple procedure " Before placing the iPod into Disk Mode, verify that it is charged.
Toggle the Hold switch on and off (set it to Hold, then turn it off again.)
Press and hold the Menu and Select buttons for at least six seconds, until the Apple logo appears.
When the Apple logo appears, release the Menu and Select buttons and immediately press and hold the Select and the Play/Pause buttons until the Disk Mode screen appears.
Connect the iPod to your computer; the screen on the iPod will should say "Do not disconnect".
If you are having difficulty putting your iPod into Disk Mode, set it on a flat surface. Make sure that the finger pressing the Select button is not touching the Click Wheel. Also make sure that you are pressing the Play/Pause button toward the outside of the Click Wheel and not near the center. If you are still unable to put your iPod into Disk Mode, use one finger from one hand to press the Select button, and one finger from the other hand to press the Play/Pause button." If that does not work, I believe it is time to disassemble your iPod. If you can, get a USB-to-Zif adapter (about $5 on ebay) and check to see if your computer can/will recognize the iPod drive as an additional HDD. If it is not recognized, you will need a new drive. If it is recognized, check for errors on your HDD and try to format the drive. If you need to replace the drive, also change the HDD cable. If the drive should function without any problems, than I would go ahead and replace the logic board.