Okay I
think I might have fixed my game, thought I'd let everyone know how in case anyone else is searching the same problem (and I did search this forum, in fact its the #1 site that comes up when I google sims problems/non-problems!) I've had 2-3 successful saves of my game since encountering and hopefully solving this problem. My main problem was my game would not save, it would freeze up during save, although there was no error code.
-1
I reverted back to an OLD save. In your save file /documents/electronicarts/sims3/saves I moved bridgeport.sims3 to my desktop, and then changed bridgeport.sims3.backup to bridgeport.sims3. This sent me back to an older save but that's okay because it was a good save.
-2 I turned off anything that I thought might contribute to using up memory/ram including; automatic memories, story progression, weather, also used my mod to "Destroyalltownies" (Killed 89), and "Towderelicts" (Towed 13), and finally "fixall" to fix game problems. It fixed 2 bad sims and 2 other errors. (I may even destroy all NPCs if it comes down to that)
-3 Instead of saving, I hit "Save as" and create "Bridgeport1" and "Bridgeport2" and alternate back and forth.
-4 Installed a program on my computer that boosts game play experience by stopping unnecessary apps and services. I also disable my anti-virus when I'm playing and I play in a windowed game, although I think I could get away with full screen. I have most of my graphics at medium to low, except sims and textures which are high.
-5 As crazy as this sounds I have a fan pointed on my laptop when I play the game and believe it or not it helps it keep cooler. I dont know if it helps my laptop or not but I'd like to think so.
Hope this helps.
ETA: Got error code 12 tonight trying to save after changing an outfit. Unreal. I hate this game. Why do I bother? Guess time to revert to yet another old save. Dont get it. I thought error 12 had to do with not enough ram. I have a 64 bit system with 4GB ram. *sigh*