I use Virtualdub for video editing.
Super works too sometimes.
All these convertors don't do that much actually, it all depends on the encoder and decoder codecs you have on your computer. Converters are all just cosmetic GUIs most of the time.
If you want a free video converter, hang out and check
http://www.giveawayoftheday.com/ and you'll usually find a "pay for" one that is given away for free one day at least a few times a month.