If you want the trilogy + Animatrix on standard Blu-ray, then you should go with either the Ultimate Matrix Collection or the 4 Film Favorites: The Matrix Collection box sets.
The above two are both US editions, but yeah, the Matrix Blu-rays are all region free, so even if they're released in region B territories - such as the UK and the rest of Europe - it's the same discs that are available in North America.
People still do unboxing vids? What is this, 2010?
Also, if you don't have the The Ultimate Matrix Collection, you're doing it wrong.
This Matrix collection is way better in my opinion (caution Amazon link)