I have found a useful free video converter software. Its great for converting flv files to avi/mpeg/mov. It works quite well for a free video converter. I was able to convert videos from one format to another without any major issues.

WinFF http://winff.org

WinFF is a GUI for the command line video converter, FFMPEG. It will convert most any video file that FFmpeg will convert. WinFF does multiple files in multiple formats at one time. You can for example convert mpeg’s, flv’s, and mov’s, all into avi’s all at once.

Easy to use interface.
Fast (Winff does not hinder FFmpeg in anyway).
High quality output.
Converts multiple different files all to the same format at once.
Convert video to audio.
Convert between audio formats.
No external codecs needed.
Includes a variety of preset conversion settings for common formats and devices.
Supports FFmpeg’s Multithreading for dual core processers
Multilingual, available in over 10 languages