Ok, taking away coolings and plugging 220 VAC unto your mainboard are just pulling your leg for posting without capital letters, commas or perioids.
As previously mentioned by DaLagga, on Windows machines you can always take a screenshot by pressing Print Screen (PrtSc) key, usually located to the upper right of your keyboard.
Then, you'd like to (pause game and) open image editing program (MS Paint for masochists, IrfanView is pretty good). Edit->Paste. And save the image.
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Posting the image on the web does require you to upload it into a server, like ImageShack or PhotoBucket. Or your own homepages. Then, you write down the URL, or web address of the picture on the server, and put it on your post between the img tags.
And oh, if you want to post the image, you MUST save it in JPEG (.jpg) or GIF (.gif) format!