Ah....boats and diving is what I love!
I will disagree only slightly with the advice so far. Most any class you enroll in will require you to arrive with mask, snorkel, and fins. They don't want to have to deal with masks not fitting, fin size fitting, etc., etc. It also saves you and the misses time and aggravation trying to find a mask that does not leak, etc. It is really annoying to have a leaking mask and will distract you from things you need to be learning.
If you learn to dive in the PAC NW - everywhere else will be a piece of cake (short of say the North Pole). However, it will require more gear, more lead weight to sink your thick thermal protection, will be less comfortable, and requires more work lugging the gear. Diving in the cold is almost 100% different than diving in the tropics. In the tropics you can wear a t-shirt, bathing suit, BC, tank, reg, mask, snorkel, fins and maybe 15lbs of lead and you're good to go. In the cold you are wearing the above plus double the lead weight (at least), a 7mm suit, a hood, neoprene boots, and 7mm gloves that changes the feel of diving and makes handling your gear more difficult. Think Sleestack hands from that old Saturday morning show...Land of the Lost.
If the misses is used to warm water diving, it may not be the best idea to reintroduce her to diving in cold water initially. Just talking with the boys here...but we know how important it is to create a good experience for the Admiral because this ultimately leads to US having a better time too. Unless you both know you want to dive near home I would suggest the referral program. (Pool book work here, then 4 cert dives in G.C.) If you definitely plan to dive at home, then definitely get your full certification at home. Just keep in mind the dramatic differences in experience for you and the Admiral.