For video you need a screen-capturing software, like Camtasia, you can google that and you'll see.
If you want to grab some screenshots of your Maya window, well, an easy way is to press that "Prt Scr" button you have on your keyboard, then you can simply create a document in photoshop or even in paint to paste your screen.
I don't think you intend it this way, but this could easily be something that could very quickly get into a touchy subject of anything from direct competition to DT or even possible piracy so I'm going to go ahead and close down this thread. Feel free to shoot me a PM if you have any questions or concerns about this. Thanks!