Instructions
Verify that the type of media you are attempting to play is actually a recognized format for the slim version of the PlayStation 3. For example, certain models of the "fat" PlayStation 3 were capable of playing games designed for the PlayStation 2. However, no slim versions of the console are backward-compatible with PlayStation 2 games. All versions are compatible with PlayStation 1 games, however.
Visit the official PlayStation blog (see Resources) and make sure the problem you're having isn't affecting all consoles. For example, in April 2011, the PlayStation Network was taken offline due to malicious activity. No PlayStation 3 owner anywhere in the world was able to access the PlayStation Network during this downtime. The official blog provides regular updates for these events, and can help you determine whether a problem you're experiencing is one with Sony's network or one with your specific console.
Restore the settings on your console back to their original defaults. If you've recently updated the settings on your slim PlayStation 3 and now are having a hard time watching movies or playing games, a restore will fix this. Open the "Settings" menu on the console's main screen and select "Restore Default Settings."
Roll your PlayStation 3 back to its original configuration. The slim version of the PlayStation 3 includes an option that allows users to restore the unit to the exact way it operated the first time it was turned on. This deletes all of your hard drive data and formats the entire system, and is more thorough than a regular settings reset. Open the "Settings" menu on the console's main screen and select "Restore PS3 System."