i recommend bigasoft youtobe downloader pro
with it, 你 can easily achieve:
Download YouTube video, 音乐 video in HD 1080p/720p, 3D 或者 stand definition 360p/480p
Download video from all 流行的 video sites like Facebook, 谷歌 Videos, Metacafe, eHow, Vimeo, MTV, BBC, Dailymotion, etc.
One-step download and convert YouTube 视频 and other online video to almost all 流行的 video formats including MP4, AVI, MPG, WMV 或者 HD MP4 (H.264, Xvid), HD AVI (Xvid), DV, ProRes, 3GP, MOV, MKV, VOB, RMVB and etc
Fast download and convert YouTube video, 音乐 video to all 流行的 audio formats like M4A, WAV, WMA, AIFF, FLAC, AAC, MP3, AC3, OGG, RA, MP2 and etc.
Windows version at
link Mac version at
link Step 由 step guide on how to use it at
link