I use iWisoft swf to video converter to convert flash swf to video files. It supports converting swf to avi, wmv, flv, mov, mpeg, mp4, 3gp video. Beside swf to video conversion, it allows you to convert swf to audio in mp3, wma, wav, ogg, etc and convert swf to gif, jpeg, png, bmp, animated gif, etc. It's good quality and easy to use.
And it also has useful editing function, such as crop swf movie, add watermark, clip segments, set advanced output video and audio parameters, batch conversion, free download online swf files and so on.