From this page, you can download any Youtube video up to 20 Gigabytes. But before you start downloading, here are some tips:

1. After you download the video, you can rename and save it anywhere you want, such as myfavoritevideo1.flv or myfavoritevideo1.mp4

2. To play the downloaded videos, you may need to install a video player, such as the VLC media player.

3. You need to have the HTML source of the Youtube video web page to start downloading, for example, the HTML code for this sample video at http://www.youtube.com/watch?v=WEjrle_bl6U.
To download a YouTube video, you just need to follow the 3 steps below:
Step 1 - Open the web page of your Youtube video in the browser
Step 2 -
Step 3 - Click the Submit button or press Ctrl+Enter key to start downloading.
Option - Start downloading the video file automatically when it is ready.