Suddenly going blank (relating to computer screens) is probably a Stop Error. It could also be a hard drive failure, although hard drives tend to give a few warnings before expiring.
Are you able to fettle the lid when you power on to see if you can impart a change in the start behaviour to the laptop? You may have a dodgy connection. Power supply snag is also a player.
Failed video card or LCD backlight failure are other causes of black screens, although probably not relevant here.
Links
HERE, to troubleshoot the restart snag, and
HERE for deeper fault find and identification. (If ever you get to the desktop) At 5 years old, you MAY have a loose connection on the mobo due to thermal expansion/contraction.
Ebuyer/Dabs/Novatech are doing some good deals!