Don' worry, here we have the solution and it's called Video Converter for Windows. Its name says everything about it. You can convert any video format to another in just one click. You only have to choose the input video and choose the output video format and quality. If you don't know the format your device needs, don' worry, Video Converter for Windows includes a large list of devices, then you only have to choose yours and it will select the best format and quality for it.
MPEG, WMV, 3GP, AVI, RM, AAC... they are all welcome to Video Converter for Windows. You can convert from AVI to 3GP, from 3GP to AVI, form AVI to MPG, from MPG to 3GP, etc. Furthermore, you can edit videos by changing brightness, contrast, saturation, cropping video and more, as well as perform a batch conversion, just add videos to the conversion list and press start.
Finally, you can extract audio from your favourite videos, that means you can convert from AVI, MPG or 3GP to MP3 or WAV.