How to take screenshot of an error on Vista, Windows XP, Windows 8 & Windows 7
You would want to click on the error window.
In other to take a screenshot of the entire screen, go ahead and press the Print Screen (it could also be labeled as PrtScn or PrtScrn) which is found near the top, to the right of all the F keys (F1, F2, e.t.c) and often in line with the arrow keys.
To capture a screenshot of only the currently active program, press and hold the Alt key (located on either side of the space bar), then select Print Screen.
To view this screenshot further or save as an image, you can use Microsoft Paint (Paint) or any other graphics program. The Paint program is mostly recommended.
To open Paint Program on your system – Go to Start -> All Programs -> Accessories->Paint
When you are in Paint at a blank page click on Edit and then click on Paste and your screen shot will appear on the blank page.
To save, just go through the usual steps for saving a picture or graphics item (for example, click File, then Save)
Choose the desired location (drive/folder) to save the file. Default location is Desktop. Write the desired name in the File Name. You can also select the desired image type by clicking on Save as type option from the drop-down menu. For example here we are saving file ‘screenshot01’ as type .PNG (recommended).