IMTU, depressurization is standard. The crew goes into vacc suits. Mechanical counter pressure vacc suits are a lot better then today's spacesuits, and don't impair movement or dexterity to a significant degree. Large vacuum pumps (yes, vacuum pumps exist today) remove the atmosphere from the ship, and put it into storage tanks as compressed air at several hundred PSI. I did the math (I did the math for a lot of things, for that matter), and the tanks don't take up excessive volume. The tanks have room for twice the normal amount of atmosphere used to pressurize the hull, so half of them leave port with spare atmosphere in them, for a 100% reserve. The tanks could get hit, but there are a dozen or two of them (or more).
The real benefit is that operations in a compartment aren't impaired due to decompression, only by the actual damage of important components in that compartment. (And that's a big difference - a hit usually only damages part of the equipment in a compartment, but depressurizes it, and likely the compartment behind it as well).
Drives will be built to run in a vacuum, and there are already electronics that operate in a vacuum in space today.
After a battle, the crew will patch up a few compartments (namely the heads), so that the crew can eat, drink, and contribute to water recycling. Depending on the damage, only enough compartments to get by until the ship gets back to port for repairs will be patched. If the ship isn't heavily damaged, the crew may patch up all compartments instead and continue on with it's mission.
On warships, spare parts, and metal plates and beams, are lashed to the overhead (ceiling) wherever there's space. In my warships designs IMTU, at least, the 10ft deck spacing in crew areas is composed of a 2ft deep underfloor area for life support, and all the other ship functions that don't get their own space on the deckplan. The 8ft above that is crew spaces, but the last foot or so below the overhead is filled with spare parts and the like ties to the ceiling, so the crew only gets about 7ft of height to live in. Of course, engineering area, holds, boat decks and the like don't have any of this.
How fast a crew can depressurize their hull is a mark of their skill. It takes about 5-7 minutes for the pumps to work in any case, the real difference being how long it takes for the crew to be ready to use them.
The hull is normally maintained at .7 atmospheres (on Imperial ships, anyway), and everyone needs to be in a vacc suit before the pressure drops below about .4 atmospheres.
Every crewman has a vacc suit at both his quarters, and his duty station. The crew on watch (there are 2 watches, port and starboard) begins preparing the ship for battle. The crew off watch either gets into their vacc suit at their quarters, the goes to their duty station, or goes to their duty station without putting on a vacc suit. Once a crewman off watch arrives at his station, the crewman on watch already there then puts on his vacc suit. The crewman arriving takes over while he does so. If the crewman arriving doesn't have a vacc suit on, then he puts his on after the crewman already there has his on. (But he would have arrived a minute or two sooner then if he put his vacc suit on at his quarters).
This ensures that the process of preparing the ship for battle isn't interrupted, and all stations are manned the entire time.
A crack ship starts depressurization as they call general quarters, with the entire crew in vacc suits by the time the pumps bring the pressure down to .4 atmospheres. Less skilled crews, they take longer. . .
Sorry if I've rambled. i ought to write an article or book on all this.