I am using total video converter. But you can use any converter as there are many available on net nowadays. - Digital -
BoilSoft Converter could help you in conversion, DVD quality however is much better then the other formats.
I tell simply google it.. Even there are online vedio converting sites which can make your work more easier..
All video converter, likedoremisoft, ,iorgsoft, higosoft video converter can help you to do this. You can free download and have a trial verison. And choose the best one .