I have a custom neighborhood that I added all three premade universities to. La Fiesta Tech and Sim State University were fine, but somehow Academie Le Tour has ended up corrupt - Delilah O'Feefe started up with no Wants, generic Fears (e.g. Get Sick, Have an Accident), and the wrong LTW (in the Culinary career when Sims Wikia says it should be in the Criminal career). Her memories and relationships seem to be intact and she still has the proper aspiration. Checking other Sims in Academie Le Tour through SimPE shows that some of them also have the wrong LTW, though not all of them.

My mistake was not backing up regularly on the computer in question, so I don't think I have anything I can restore to (though it probably wouldn't make much difference since I hadn't played Academie Le Tour at all prior to this).

I don't really know the technical side of corruption, and the subhood seems to have been corrupt from its creation, so I don't know if there's some way of fixing it with SimPE or not. My other thought is to kill off any corrupt Sims, but I know that if the character files are messed up, that probably isn't going to solve anything.

Is there some way of slowing the corruption so that it doesn't quickly spread to the main 'hood or other university subhoods?

I wouldn't worry about the LTW thing. You can find a lot of nonsense and half-truth on the Wiki, depending on who edited it last. I've got a Delilah who wants the Gaming career and one who wants to be a City Planner. I seldom get a University sim whose LTW matches what the Wiki says, and I think it's assigned randomly on first load of the character, along with turn-ons/turn-offs and other features that post-date university.Culinary isn't normally a Knowledge LTW, but you may have a mod for that. Just give her what you want her to have. No wants is a problem if it persists, but it doesn't necessarily mean a corrupt sim. Sometimes it's a mod conflict. Sometimes it's a bad lot. Sometimes the game just stutters and the wants thing fixes itself. After a little gameplay, the training mechanism will kick in and she'll get less generic Wants.

Strictly speaking, corruption arises because data gets assigned or used in an inappropriate way. This is almost always because a character is deleted, leaving data behind; or because a character has incomplete data for some reason, or because data gets damaged due to some computer event (such as a crash while saving). The organizing principle of sim identity is the Sim ID Number. This is supposed to be unique. Due to a design flaw, when a sim is deleted, some data are left behind, still using that ID Number; but the number is perceived by the program as being free to re-use. The result is that, for instance, a number for which data appropriate to an adult male sim may be reassigned to a female cat sim, or a newborn baby, and that data will be used by the new sim regardless of whether it makes sense. Similarly, if a sim's data are damaged, it may render it incapable of behaving normally.

Another form of "corruption" occurs due to normal data deterioration. All your programs accumulate a certain amount of wear and tear on their data; but most programs are simple enough, or robust enough, for this not to be a major problem. The Sims 2, however, is an extremely complicated program even before you add in mods and mod combinations, different user interfaces, and user peculiarities or experiments that were never anticipated by the programmers. So you get a certain amount of virtual grit in your data. Some of this kind of corruption, and the more detectable and isolatable forms of major corruption, can be dealt with by a program called Mootilda, called the HoodChecker.

To minimize corruption, make sure you have the truly essential mods, the ones like "nounlinkondelete" and "nocorruptdeath" that prevent some of the more common types of accidental data deletion. Never delete characters from a neighborhood you want to keep. And on some sort of schedule that makes sense for your gaming habit, make it a habit back up your neighborhood, run the HoodChecker (on Remove setting) on it, and then resume play. While playing, you can also use editing tools like the batbox to check for and delete corrupt memories and fix some problems.

Always back up your neighborhood and run HoodChecker before making major changes like adding a subhood or a major mod (such as ACR or a multi-PT), so you can revert if anything goes wrong.

And when little glitches arise, if you know you haven't done anything terrible like send someone to a lot bin - troubleshoot, clean up the effects, and keep rolling. Because you can't play soccer with a clean ball! Stressing about this stuff is no fun, so once you've developed some good habits, don't spoil your own fun by stressing about it.

Nope, when the game adds a subhood all of the sim's information is added to the primary neighbourhood and used from there, Only the neighbourhood view and lot information is used from the subhood's file. If there is corruption then it already is in the main 'hood.