I rendered a file of mine as an MPG-1 file.  The first time I did it the file came out at about 148 MB.  When I did it a different time it, as an mpg-1, it came out as about 57 MB.  I really have no clue what caused this.
Techinical Support said to check the bitrate and resolution, but I never changed them between the two times I rendered.
To top it all off I am trying to copy the video to an e-book program as a clip and it won't work with the smaller file.  So any videos I clip to e-book from this point on all turn out smaller and hence...will not work.
Any suggestions?