Can we add an Internet link to Mathematica 7 or any link ? Can I add a video or picture ?
[http://www.wolfram.com/broadcast/video.php?c=97&v=314]
Try Insert > Hyperlink and Insert > Picture. You could theoretically add a video as an Animate, but it would be best just to link to it.
http://www.wolfram.com/broadcast/s?sx=mathematica+7