Screenpresso is the best software to capture edit and share screenshots and HD videos under Windows. Screenpresso is a new tool dedicated to screen capture with features that help users share screenshots on email and Twitter easily. It also provides a new way of capturing the screen using a single hot key, an history and a built-in editor like SnagIt. Download required but will run in a portable version from a thumbdrive. Free version, but video capture is 20 seconds max and you can only edit once.