i recommend bigasoft Youtube downloader pro
with it, toi can easily achieve:
Download YouTube video, musique video in HD 1080p/720p, 3D ou stand definition 360p/480p
Download video from all populaire video sites like Facebook, Google Videos, Metacafe, eHow, Vimeo, MTV, BBC, Dailymotion, etc.
One-step download and convert YouTube vidéos and other online video to almost all populaire video formats including MP4, AVI, MPG, WMV ou HD MP4 (H.264, Xvid), HD AVI (Xvid), DV, ProRes, 3GP, MOV, MKV, VOB, RMVB and etc
Fast download and convert YouTube video, musique video to all populaire 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 par step guide on how to use it at
link