I know a Total Video Converter is very good. You can try it.
Aiprosoft Total Video Converter is a complete solution for video conversion which supports reading, playing all kinds of video and audio formats and converting them to the popular video formats.
This Total Video Converter integrates all the functions of HD video converter and general video converter, which converts almost all High-Definition and Standard-Definition video formats (AVI, MPEG, WMV, DivX, MP4, H.264/AVC, AVCHD, MKV, RM, MOV, XviD, 3GP, etc.) from one to another. This all-in-one video converter also extract audios from above video files and convert between multi-format audio files including MP3, WMA, WAV, RA, M4A, AAC, AC3 and so on.