Most websites, such as the one listed above, do not allow you to download HD video for free. However, the free program youtube-dl can download any available YouTube video format to your computer, including the HD version.
HD 159 18:30 
HD 109 16:24 
HD 117 10:00 
HD 110 05:17 
HD 86 07:49 
HD 118 11:10 
HD 173 10:25 
HD 72 17:48 
HD 87 09:38 
HD 70 10:05 
HD 81 01:48 
HD 103 15:07 
HD 49 02:55 
HD 86 10:48 
HD 134 15:11 
HD 203 10:27