Failing to startup

[ItzTez]

My little sister's were recently playing on our home PC, a Dell all in one (in not sure on the model) and they decided to press the sleep button on the keyboard. They panicked and turned the PC off. When they tried to turn it on it would do the Dell logo, and then it would show a loading screen (just black and in the middle bottom a loading thing) then right after this it would be on, exept all we could see is a blackish blueish screen. We could see our pointer and everything but we couldn't see the actual display or anything. I asked my brother, who knows a bit more about computers then me, and he did some work on it. At this point in time when we press the power button, it stays black with no response. Any help is greatly appreciated.

 

[LukeFatwalker]

Extremely vague here, what work did the brother do?

If the machine won't power on at all it's likely hardware damage. If it powers on but won't load into Windows, the MBR is corrupt and needs to be fixed.

Sadly there's no information here to prescribe the issue and subsequently a fix. Find out what 'work' the brother did and come back for a (hopefully) more specific answer.