I think that
AVS Video Converter from
avs-video-tools.htm" rel="nofollow" target="_new">
AVS Video Tools is the best tool for this task.
All you need is just to open your files, select ouput format and click convert now.
In several minuts, you’ll have one file.
The very good thing is that
AVS Video Converter supports tones of video formats: No one program supports so many video formats:
*.avi, *.divx, *.xvid, *.ifo, *.vob, *.vro, *.mp4, *.m4v, *.h263, *.h264, *.mpeg, *.mpg, *.m1v, *.m2v, *.dat, *.mpe, *.3gp, *.3g2, *.3gpp, *.3gp2, *.wmv, *.wmv-hd, *.asf, *.mov, *.qt, *.rm, *.rmvb, *.swf, *.dvr-ms, *.dv, *.dif, *.flv, *.mkv, *.ogm.
You can even edit you files with this tool: cut, trim, etc. I think that it is the only video converter that has timeline for fast editing tasks.