On 747 that do not have new business class & wireless installed the IFE is very limited hence they offer in-seat player (installed inside the armrest) and have library of several additional titles with special first class menu that FA hand out at boarding.
On 340/330 all IFE is how to say it automated ... althoiguht the tiles may be the same (I never checked) you do not need casette to put in to your palyer.
That's whyI was always under the improession that on 747 IFE is "reacher" in choice and titles...
So maybe I was wrong all these years ... well we learn all live and than you know what happens
(did not mean to be dramatic)