solutions to compression

hi there -

I have been reading and learning from this site for many years and have always found the answers I needed with the exception of compression. So, thank you for dealing with my ignorance. :)

It seems like there would be a program that would allow you to specify what the actual file size you want to compress to. Like if I had a 16GB HD file that I wanted down to exactly 4.7 for DVD or that same file down to the 2GB limitations of YouTube or Vimeo.

Perhaps there is such a solution and I have totally missed it. Currently I use AE to compress files down for uploading but they always turn out to be so pixelated. Apple Compressor is such a complex program that I don't even now where to begin but I am willing to try if I can just get in the right direction.

Any help would be much appreciated.
rand