I used essentially the same script you have in the intro, but this is what I used:

Code:
ffmpeg -i "${input_file}" -f mp4 -vcodec mpeg4 -maxrate 1000 -b 700 -qmin 3 -qmax 5 -bufsize 4096 -g 300 -acodec aac -ab 192 -s 320x240 -aspect 4:3 "${output_file_name}.mov"