Where is the print screen button on a dell laptop keyboard?

It's above F10 and named "Prnt Scrn".

Use the print screen key, u will get the full screen capture, press CTRL+Pr Scrn button, uwill get active window.

But if u wanna capture anything on the screen, i think the print screen button couldnot help u. So i recommend u try PCHand Screen Caputre. It could help u capture anything. Im using it, it is easy to use, even for a novice. I think it is pretty good. Hope it could help.