I.Remove the A/C power code from the Laptop
Push the power button it should shutdown.if not close the laptop and take the battery out. It should shut down now.
check http://www.insidemylaptop.com/ that would help. Good Luck
II. Put the cable back on and push the power button on and then press F10 continously (Key might vary). This will bring BIOS UP. After the BIOS Setup Utility displays, use the Right Arrow key to select the Diagnostics menu. Select HDD Self-Test options.Select Notebook Hard Drive. Enter tocontinue. The Hard Drive Self Test executes a Quick test , a Comprehensive test, and a SMART test. At the end of the test, you will know the status of the hard drive whether it is passed or failed. In case it is failed you need to replace it.
Go to the Diagnostic log and check the error code. This test you will have to do for the RAM. Once done you will know whether your HD or RAM is at fault.If both are error free then use a bootable CD and try to boot it. You may have the change the boot oder. Good Luck