Producing Your Video (aka "rendering")
First, Consider Making these 3 Decisions for choosing the format you produce.
1. Define how you will use this video (size of file & size of quality viewing)
Keep it on your computer for your use
Do you want high quality with a smaller file: Try MP4 or basic mpg
Burn a DVD: Must be mpg
Attach it to an e-mail: must be compatible with many computers. Try MP4 or Quicktime MOV
Post it on a web site: must be streaming form of a compatible format.
Strip out video and convert to MP3 as a separate file.
2. Decide if you will want to use the video in more than one way. Produce one format at a time out of your editing program or use a converter program to produce the video in several different formats (including audio MP3) in one session.
3. Decide if you want to keep the finished video for long term. Produce the video in a format that will have the highest quality and can be converted ("transcoded") later to different format.
Second, choose a format for your produced video that will allow you to do what you have decided are your needs.