The Extreme Edition has a new transfer. I don't know about the special features. You can watch the Extreme...or EXTREME! edition in Hi-Def on the internet, which is a cool feature. I don't know if Brazil uses PAL or NTSC, but I would buy NTSC just so I don't get PAL speed-up.
EzyDVD's 3-movie pack is only a slipcase packaging containing the 3 movies, and misses out on the 2-disc special edition of Terminator because that went OOP and was replaced by a single-disc version.
The Ultimate Edition has DTS and DD tracks on it, as well as tons of special features. The transfer is all that is lacking on that edition.
The Extreme Edition has an amazing new picture master(one of the best out there in my opinion) and the DD track from the Ultimate Edition. It also has a wonderful audio commentary by James Cameron on it, his first ever.
I would recommend getting the Extreme, mainly for the much improved transfer, although the extras on the UE are excellent, but to me the movie is king.
Yes, the R1 Terminator SE is a DVD-14. Only T2 and T3 have been released in 2 disc versions, and the UE of T2 was originally released as a DVD-18 (the version I own).
The extended version of T2 is on both the Ultimate and Extreme Editions. There's also a super-extended version with an alternate ending thta's only on the Ultimate (though the scenes are included as extras on the Extreme).
I doubt we'll see a Terminator Trilogy in the US any time soon because 3 different studios own the DVD distrubution rights to the 3 different films (Terminator - MGM, T2 - Artisan, T3 - Warner Brothers).
Buy it on ebay. Or, It turns up used around here. If you want, I'm sure I could get you one for ~$14US (~43 Reais ) plus whatever it costs to ship to Brazil.