Take multiple screenshots of predefined area and save as gif - vb .net

Hello coders, I need a windows standalone program that will take multiple screenshots of a predefined area and save as a .gif file. So if the user wanted to save a clip from a youtube video, he would select the video playing by clicking and dragging the cursor to select the video, then press record and start the video. Once the user pressed the stop button, the screenshots of the selected area would be saved as a gif file. I don't mind if you use active x controls or have suggestions on how to make this easier. I need this written for Visual Basic .net. Thanks