> a way to have a cohort of teachers all have access to one repo of common course content (used across about 30 courses),
Do you mean just files or does the repo have other content like forums, lessons, etc.?
If just files, have a look at the http://docs.moodle.org/en/File_system_repository
> and also have the ability to easily download and burn all this content on a DVD for the grads at the end of the program.
The usual method is to tell Moodle to zip the whole directory tree to a single file before downloading. I've just checked the file system repository in a Moodle 2.4 and couldn't find the zip function. A workaround would be to distribute a generic (S)FTP
account amoung the undergrads so that they can download the files themselves. Since the files names in the file system repository are not hashed, there shouldn't be a problem.