hello i have an acer z5600 all in one with windows 7.I did not buy it new.The problem is it gets hot and will shut off.sometimes it will come up with a blue screen and say fatal error...once it cools down it starts no problem.Can i gets some advice on where to begin.i know nothing about these these computers.thanks

Generally, heat problems are due to heat trapping dust clogging up the vents and heatsinks. So you can start by making sure the vents are clean and there is enough clearance around the computer.

I am unable to find a manual for this computer - in fact information on any Acer all-in-one is hard to find. But I would look in your manual to see if there is a way to open the case to expose the interior for cleaning. Assuming the case has a cooling fan, they draw in dust too. If not comfortable opening the case, you may have to take it to a shop for professional cleaning.

You might consider using a desk fan blowing air from side to side to see if that helps too.

Note if the interior and vents are clean, this could be a failing component, no longer able to deal with normal heat, let alone high heat problems.