The idea of taking a screenshot --a computer snapshot of whatever happens to be on your monitor-- is often touted as a great way to prove to the casino that what you said happened really did, be it winnings or screwed-up software or whatever.
The basics of screenshots are easy. On a PC you just look for the PrtScn button up near your F10 or F12 key. Press PrtScn and a copy of your desktop is instantly copied to your Clipboard. Great, now what?
Ok, open any graphics program, even Microsoft's Paint will suffice. Assuming you are using Paint, just click on the Edit menu and select Paste. Voila! A screenshot!
Of course if you're using some other graphics program the procedure will be slightly different. In Photoshop for instance you'd select New on the File menu then Paste.
What you get using the PrtScn approach is a full shot of your screen: toolbars, wallpaper, the works. Everything on your screen is captured, for better or worse. And since Windows does screenshots in BMP format the files can be quite chubby.
It's worth noting that casinos generally have no official policy on the screenshot matter. At best they might be interested to see your screenshot but it's unlikely that they'll take it as stand-alone proof of anything. I contacted six major casinos and asked them to comment on the subject: none replied.
Part of the reason for casino's skepticism is that it's incredibly easy to doctor a screenshot. Of course they know this. (For more on this see the Screenshots discussion on our message boards).
So what if you wanted just a particular window, or dialogue box? Windows documentation states that Alt-PrtScn is supposed to do just that but it's been my experience that this is unreliable. I suspect this is due to the fact that many programs are watching very carefully what you do with the Alt button and hence Windows sees the PrtScn part but misses the Alt part.
There are some pretty good programs out there to help you if you want to get serious about this screen capture business. I've used SnagIt and it has more screen capture features than any non-professional will ever need. I've also heard good things about Hypersnap-DX.