Wow, that file size is huuuge. I'm curious: how many sim weeks/generations into the game are you? My largest one at the moment is 160MB, and that game is about 5 generations and the gameplay is starting to slow down a bit...
I don't have too much travelling experience, but I used to get that "The Sims 3 has stopped working" crash a lot. In your case, it might be the file size, but better trust someone with some technical knowledge rather than me.
I tried all sorts of things to stop the crashing (clearing cache files often, DEP exceptions, etc etc) without any visible results, but it stopped when I installed Nraas' Overwatch mod (read more about Nraas
here). I also got Traveler and ErrorTrap mods later. They might help you, too. Of course, I understand that not everyone want to mod their game.
PolarBair - how long have you waited for the file to load?
I've noticed that as long as the tips keep changing, the game is going somewhere... sometimes it takes a very long time to load. Especially if you have cleared caches. Sometimes I notice the tips "freeze" and even though the music is still playing, the loading really is stuck. Those times I have to force shut my game. But, I once had my file load about 10-15 minutes for some reason (normally my loading times are only a couple of minutes max), and the loading bar didn't seem to advance... it still loaded eventually.