Chosen Solution
Why my system doesn’t boot?when i press power on the screen light is turn on and picture apple it’s show and the role under apple will stop then system is locked and I can not do anything, only I can push power key for seconds to turn my system off. I’m Sorry about my tribble english writing, I’m not an english native speaker. Best regards.
First guess is a faulty hard disk. If you have access to another Mac, connect them with a firewire cable, start yours in “target mode” by holding down the T key and see if the disk mounts on the other Mac. Use the drive utility to check your drive. Please report on your findings so we can help from there. Remote troubleshooting is never easy ;-)