I've never understood either why Fox has released some of its films in Spain but not the US or UK. I have Spanish DVDs of a couple of Fox films which were otherwise unavailable in the States, Woman's World and Night People, and they are of excellent quality -- perfect picture, color, sound, and widescreen. (Night People has since come out on the Fox Cinema Archives line in the States -- but not widescreen!) I also have a great Spanish DVD of the 1954 Paramount film Secret of the Incas.
On the other hand, I have the Spanish DVD of the 1953 Universal film The Mississippi Gambler -- made by Universal, not a bootleg -- and it's a pretty poor transfer. You never can tell.
I've even found American films available in the UK but not the US (or sometimes, in their original widescreen formats in the UK while they're not done that way in the US), plus some British films available in the States but not in Britain. The whole business is screwy.