1. have you any anti virus? if not please scan your pc with update antivirus.
2. check your cooling fan. does it become hot so quick? if yes, please check it for cool.
3. plz check your ram.

you can check every thing in other pc of your any friend. then you can find out what was corrupted.

you mean your pc not start. so plz check the cable of power button. or you can unplug it and try to start it manually by connect those 2 pin by any thing. check the power cable of mother board.

try to check the port and check a another harddisk in this machine.

I didn't read all post. some reason do it:
1. disconnect hard disk with motherboard
2. 1st Boot device problem
3. operating system damage
or hard disk damage

the cd you run with your laptop. but your pc didn't read. please check your cd rom. or check your cd other pc.