I'm no expert, but it depends on whether you are making the film for the web or for DVD/VCD. I'm assuming it's for the web, so re-encode with a
lower bitrate(s) and experiment to find the lowest possible rate within your acceptable limits of quailty loss. Don't output as .avi , you need to
compress it, so output as an mpeg, or for even more compression, .ram/.rm (Real Player), or .wmv (Windows Media Video) or Quicktime.