Sims have always become obsessed with things- bubble baths, getting water, writing in their diary, turning on radios and tvs. I have a Sim right now who is obsessed with his pool table. Left to themselves, they are likely to starve to death while they play computer games or pass out in their dinner because they couldn't be bothered to go to bed. They frequently try to write in their diary when other Sims are around and just spend hours sitting there trying to hide it from the other Sims instead of writing. When my Sims become obsessive about a particular object, sometimes I remove it for awhile or I place new objects they can obsess over for a change. You can turn autonomy off if it is just irritating you too much. There are also some mods out there that help, aimed at stopping them from doing certain things at all or as much without you directing them to. I have a few myself. With Sims 2 you have to do a lot of managing. They are better at handling themselves in 2 than they were in 1, but not as well as in 3 or 4 by a long shot.
The infinite loading lot issue is usually caused by something being stuck on the lot that is corrupting it. Personally, here's what I would do (assuming this is a Maxis lot). I'd package the lot, then delete it from the world. Then I would use Sims 2 Clean Installer to install the lot again. The program shows you what is included with the lot. I would uncheck any Sims, objects, or CC that became attached to the lot that are not original to it, then install it clean. If any of the objects that were attached to the lot were CC, I would remove the CC from my computer.