There are quite a few tools available that would allow you to "de-iTunesify" your iTunes library.
Moral and ethical values aside, the most obvious candidate for this task is
MusicBrainz Picard. The thing that makes this non-trivial and requires batch automation is that iTunes very deliberately stores the media on the host machine in a near random fashion, with complete garbage filenames and directory structure.
Picard, (and many other tools, but Picard is vastly superior) can read the embedded metadata from these files and export and rename them to a sane human readable structure.
I should point out that I am presenting this as a thought experiment, as depending on your locale, and a number of other factors, what you're wanting to do is at the best morally questionable and at the worst unlawful. One posits that if you had physical copies of this media that there would be no issue at all, so it implies this is not the case and the media has been purchased solely from the iTunes store (uuuuuugh).
Regarding your films, ...I have absolutely no idea, but honestly, who wants to watch films on a 240x320 screen anyway? I am absolutely certain that there is a similar tool out there that provides the same database de-obfuscation services for video, but I am not intimately aware of any. This shall be left as an exercise for the reader.
It may pay to note, however, that there are some
VERY specific requirements regarding playing video in Rockbox, it is almost certainly not as simple as you expect it to be. Even if it wasn't locked in a crazy database with an obfuscated structure, it almost certainly isn't as simple as you expect.
The (unsupported) iPod Classic is somewhat of a special creature, as it has no dual-boot, and the original firmware is wiped out _completely_, this process is not so simple. On any of the other iPods, with audio at least, Rockbox will happily read from the iTunes database. On the Classic with Rockbox, this does not, and can not, exist.
With regard to the Database failing to initiate, and/or failing to commit, this almost certainly points to it choking on a particular file with malformed metadata. We offer a logging function in the developer options that allows you to enable logging functions which will point to which file this is.
I am sorry if you somehow got the impression that Rockbox on the iPod Classic is in a different shape than it is, but we make it pretty clear to the user on our main page (at least in my mind) that it is in no way ready for mass-market public consumption.
Hell, we don't even offer you any officially supported way to boot it, at all. You had to use a third party bootloader (which itself is also in no way intended for mass-market consumption, at all, and is actually an incredibly powerful development stub that just so happens to also be able to boot Rockbox). That should say something.
Also, remember to
BACKUP YOUR ITUNES LIBRARY AND ONLY WORK WITH THE BACKUP IF YOU ARE INTENDING TO USE ANY FORM OF METADATA MANIPULATION TOOL. I absolutely do NOT want to be held responsible for someone trashing their library with an incredibly powerful tool because they may or may not understand the implications of its use. With great power, comes great responsibilty, yadda yadda, etc. and so on.
Oh, and one last thing, the Database is completely and absolutely non-essential to media playback. We do offer a file browser. Most developers, in my experience, don't even use the Rockbox database at all, and prefer to use the file browser and leave the RAM that the database consumes available for audio buffer making the device as a whole more efficient.
[Saint]