Open the TS2UC folder inside your documents. Delete the cache files and try to reload the game. Accessory.cache amd
Groups. cache. If you have used CAS and or Bodyshop delete the cigen.package. All these can grow very large. Deleting them before you play will take time for game to reload but will clear out any problems.
Also, one of my rule of thumbs (unless you are on a very super gaming machine) is to not quit within a lot. But save the game, then go to neighborhood view and quit.
The TS2 gives you the ability to save the game, then quit while you are still in the lot, but I stopped doing that years ago unless I was on a very good machine. Just seems to have less problems if I save the lot, then go out into the neighborhood view and click quit.
ETA: If you are playing the game using Origin make sure Origin in game is turned off it's a resource hog. I think (can't remember) you have to enter Origin app to set that to off. Says something like 'while in game'.