Just use MinGW to do all files in a directory so say you have all your files in C:\ToBebzip2 it would find and bzip2 all the files you have in it and will keep the directory structure too.
To use this you'll need MinGW (
here) and MSYS (
here) If you need help here's the setup and install guild
http://www.mingw.org/wiki/InstallationHOWTOforMinGW When installing MinGW make sure you get the bzip2 lib.
Once installed open MSYS run this command
Code:
find 'C:\YOUR PATH' -type f -exec bzip2 -9 '{}' \;
So say your files/folders are in C:\bzip2 and you have the folders "models" and "maps" in it. Your path would be C:\bzip2 and it will find all the files and folders inside C:\bzip2 and .bz2 them for you.