I want to compress a 16GB folder, but what's the best method? tar.gz? tar.bz2 rar? 7z? Would the archive be smaller if I first compressed in a method, then copy the compressed archive to a new folder, then re-compressed in some other method? I need to make it fit on a DVD (output maybe 8.5GB, don't remember) but putting "4370 MB" makes the compressed file be 2.5GB part.
BTW, what's the default compression method on Ubuntu?