I just found this software today; it's a great program. And it's free!
I agree, the interface is not quite straight forward but after reading the user guide, it's very simple to use. I've been editing some videos in the wmv format with my Mac. The best output I found was a MP4 format. I think the quality has been lowered due to compression but it's still visually appealing.
Here is a link to this software :http:// www. squared5. com/
Other video editing software: http:// www. thefreecountry. com/utilities/free-video-editors. shtml