First, just leave the YouTube or MetaCafe video to play fully. By playing the full video means you are buffering the video file into your computer. The buffered video files will be stored in your computers "Temporary Internet Files" folder.
After completing (Buffering) the YouTube video files into your computer, you can copy the buffered file from your "Temporary Internet Files" folder to any other drive or folder as you wish to store those files.
Probably the YouTube files will be store in you computer as FLV format.
Now, open your "Temporary Internet Files" folder, to open it click Tools>Internet Options from Internet Explores menu. If you are using Internet Explorer-7 or later, click the "Setting" button under the header "Browsing History" from the "General" tab. Now you can find your "Temporary Internet Files" folders path as "Current Location:" you can open the folder by manually typing the location address in "Run" command or you can open the folder just clicking the "View Files".
The "Temporary Internet Files" folder will open. Now, find the YouTube video file which is in a FLV format. For easiest find, set your folder view type to "Detailed" and locate for the "*.flv" extension files. This the YouTube files actually. Copy it to any other location.
That's it. You can now play the files using a FLV Player or using your Internet Explorer.
The above will be works for all version of Windows except Windows Vista. Because, Vista's tight security will not allow you to view the Folder, where the downloaded files stores.
The above guide will also applies to Mozilla FireFox, Opera, NetScape and more.
You can download the FLV Players from the following location to play the *.flv files:
http://www.download.com/FLV-Player/3000-2139_4-10467081.html
http://www.applian.com/flvplayer/download_flv_player.php
http://www.download.com/Riva-FLV-Player/3000-13632_4-10435953.html
http://www.snapfiles.com/get/flvplayer.html
Or you can download the FLV Converters from the following locations:
http://www.soft29.com/dvd_video/video_converter/flv-converter.html
http://www.onlyfreewares.com/Audio-Video/Video-Converters/Free-FLV-to-AVI-Converter.php
http://www.ripzor.com/flvconverter.html
Note: This guide will help for MetaCafe users too.
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