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Start to finish. Line up your screen how you like it.
Press the Print Scrn Button on your keyboard, it'll be next to F12 probabably.
Then run MSPaint, and press Ctrl+V to paste the image.
If you go to www.irfanview.com you can download Irfanview, a very useful program that lets you take screen captures as well as being an excellent image viewer. It has things to automate the procedure as well as only capturing certain parts of the screen ^^