Hey thur. I figure this is the best way to do this.
GUI Version (Windows)
Click Media > Convert/Save
Type in URL of YouTube video.
Start > Run...
type, "cmd" and press enter/ok
if vlc is already added to PATH then skip the next step
type, "PATH="%PATH%;C:\Program Files (x86)\VideoLAN"" into the command line. This is important as it enables cmd.exe to be able to use vlc without vlc.exe being in the present directory. It's also possible to change the PATH variable by right clicking Computer > Properties > Advanced system settings.
It should be noted that the exact location of vlc.exe might vary from system to system. This is where it will be located in 64-bit Windows 7. In other versions of Windows it might just been in Program Files without the, "x86" part. It is also possible to have a 64-bit version of VLC that will reside in the standard Program Files folder in (64-bit) Windows 7. As long as VLC is installed on your computer, it shouldn't be that difficult to locate but you may have to change the command accordingly to what it is on your computer.
Navigate to the folder that you would like keep the your YouTube movie in and type,
"vlc -vvv http://youtube.com/someyoutubevideoe3f3fvcv3r --sout file/ogg:example.ogg"
That will create an ogg file called, "example.ogg" that is the YouTube video. Yeah.
VideoLAN/VLC 64-Bit Version (Windows. Archived version.):
Cygwin for all your mafk' command line needs :3