How do I take a screenshot of my computer screen and e-mail it?

Assuming you're using Windows, this is actually a very simple process.

Simply press the "Print Screen" button (sometimes abbreviated as "Prt Scrn") on your keyboard. Windows has now automatically copied an image of your screen to it's clipboard where it is stored temporarily until it gets replaced by anything else (e.g. text in Word, etc.).

To e-mail this to someone though, you need to now save the captured image as a graphics file. For this you'll need an image editor. You can use Window's Paint application, but it, in a word, sucks.

Fortunately for you, there is a nice free image editing application available, PhotoPlus 6. If you've not yet downloaded and installed this program, do so now.

After installing PhotoPlus (and after pressing "Print Screen" to grab an image of your screen to the clipboard), open PhotoPlus. Click cancel on the "welcome screen" if it appears. Now click on "Edit" and select "Paste as new image".

Now you can manipulate the image as you see fit, save it as a .jpg file when you're done, and mail it to your friend!