Is it a good idea to put a low-budget documentary/music video on IFilm?
Is there a better option on the Internet?

http://www.ifilm.com/

"Better" is a subjective call, so it depends on how you see it. If you're putting something on the web for the world to see though, you might as well upload it to as many places as possible. Why not upload to YouTube and Google Video as well? You're likely to get more traffic there than at iFilm.