What will happen?

It's unlikely that anyone can answer your question without you providing more information. Can you try to be more specific? What button(s) did you push or options did you select? What Operating System are you using?

Generally speaking, selecting wrong options or pushing wrong buttons could result in either some error condition, no operation, or at worst...loss of data. If you are talking about a PC, have you caused a reboot? Unlikely that you would damage hardware, though. What makes you think you could cause yourself physcial harm? Are you trying to get inside the equipment? If you do this, and cause a short out across a component or power supply, you could cause yourself harm. I would contact your tech support person before you try anything you're unsure of.

Cannot guess or read minds...so you need to supply more specific info.

one hopes he's not working in a nuclear missile silo

reminds me of the simpsons episode where homer's working from home

<computer> - press any key to continue

<homer> - oh, where's the any key