i guess i will be the first to post a reply, mostly from my short time of handgun ownership, so my opinions may not carry much weight with the experienced folks here.
based on your criteria of needs, you should actually by 6 guns, 3 for you and 3 for your wife.
1. Fun to shoot: this can be a large caliber (1911) for you (big boom) or a large capacity semi auto for more shooting without reloading, with more reload time.
this could also be a long barrel revolver (S & W 686 6" barrell) since the larger sight radius will be easier to shoot accuratley at the range or a 22 target pistol (more shooting for less $$)
2. since large calibur, long barrell and high capacity do not necessarly conceal easily, you will need to by two more to meet the conceal carry category. carry will more comfortable if you can go lightweight. the new polymer guns and allow revolvers are around a 1/2 pound unloaded. light weight guns in large calibur are not fun to shoot at a long session at the range.
also a shorter barrel (sight radius) is easier to conceal but accuracy past 7 yards is the compromize,
here i would recommend a 9mm or .40 cal in a polymer gun (LC9) or a snub nose revolver in a alloy frame (SW 642)
3. home defense. this will depend on your neighborhood and surroundings. Apartment dwellers should have something that will not create a risk for your neighbor, or the guy 2 doors down. hollowpoints reduce the risk of over penatration, and a shotgun load will also help shooting thru multiple walls.
if you are Urban inter-city or suburban home owner with children readily acccessiblity when the need arises and security from theft or small inquisitive minds should help in the decision of a bed side handgun safe or a larger gunsafe for your new collection
if you live on a farm or country estate, a long gun may meet your needs. being able to stop someone before they can get to or in your door may be a concideration.
i don't think your new obsession will be a bank breaker, make your purchases as your interest grows and you "toy funds" accumulate. start out with something that is fun to shoot (keep interest in the hobby) and inexpensive ammo. as you skills grow and confidence in the guns, find a conceal carry that will meet your reqirements for a carry weapon.