According to recent high user ratings, a free video converter: VidPie can totally satisfy all the conversion needs. You may see its strong points via http://www.vidpie.com:
Always free, totally green
Vivid and user-friendly interface
Supports ATI and NVIDIA acceleration
Supports both folder and video/audio input
Support all the standard video and audio files input
Support batch conversion to all the key formats
Free to join its community http://aunmedia.com to share any digital experience with digital enthusiasts.