It's possible that your iPod is working to some extent (since the backlight is on and the click wheel makes a sound when used), but the LCD screen is not working. First, try doing a Reset (which restarts the iPod)
Even if it is still not working, does anything change after doing the Reset?
If that does not help, when you connect it to your computer's USB and run iTunes, does it appear in the sidebar under DEVICES? If it does, select it in iTunes and try doing a Restore. The Restore button is on the iPod's Summary screen in iTunes. This will erase the iPod, reinstall its software, and set it to default settings.
If the iPod does not appear in iTunes when connected, or if doing a Restore does not solve the problem, the cause is likely to be hardware-related.