iMovie to Flash

i recently created a video using iMovie.  i exported video as a .Mov file, but for some reason I am not able to import the video to articulate video encoder, because it says i do not have the latest plug ins for windows media player and quicktime.  i then converted the .Mov file to Mpeg and i was able to import it to video enconder, i maxed out the bitrate and increased the size of the captured area, but when i open the converted flash file it looks very choppy and the quality is very low. any suggestions on how i can improve the quality of the video