Hi,
Just try professional Total Video Converter to have a try.
http://www.macdvdrippersoft.com/total-video-converter-aiseesoft.html
No Virus, No music video lagging, Fast speed, High quality.
It can convert almost any video and audio formats such as avi, wmv, flv, 3gp, mp4, rm, mov, dat, mkv, hd ts, rmvb, mpg, mpeg-1, mpeg-2, divx, xvid, asf, swf, 3g2, m4v, dv, QT, mp3, aac, ac3, wma, wav, ogg, flac, m4a, ape, etc to popular video and audio formats.
It also has powerful video editing functions such as trim, crop, effect, merge, snapshot, watermark and so on, it is also easy to use.
Just try it and I hope it can help you.