There are two alternate versions of "Who Wants to Live Forever", one hidden on each disc:
On disc one, when the picture sleeve for "Who wants..." appears on the screen, press [Enter] on your remote. This will automatically take you to an alternative video of the song featuring both the band and scenes from the "Highlander" film.
On disc two, at the [Main Menu], select [Hot Spaces]. From that menu, move the cursor to [Play All], press [Up], [Left], [Right]. This will play another version of "Who wants..", this time with the living members of Queen, and two young vocalists.