ffmpegx file shrinking and subtitles

[mystery]

Q: If I use ffmpeg to shrink a 1.5 GB avi file with subtitles (.srt) down to a 700 mb file, will the subtitles still work? (edit: and by that I mean will they still sync up correctly with the movie?)

I have a few movies that I would like to be able to fit on one CD each.

Also, I have only used ffmpeg's file compressing feature a few times and only to shave off 3-10 mb each time. I have gotten quite a bit of pixelization when i do it though. Perhaps the original movie was like this. Anyone have experiences like this? Ive been shrinking and encoding with the ffmpeg divix codec.

Thanks!

[major]

The subtitles will still work. To compress a file, you should lower the bitrate, but you will logically end up with some quality loss.