Welcome to the forum, Antony.

Yes, your house and family files are in the User Data folder. If you're using more than one neighborhood in your game, the second neighborhood would be in the User Data 2 folder, etc. You might want to save the entire User Data folder, since it also contains your family photographs and the web pages that the game can create for your families.

If you think that the problem is because an object is crashing your game, rather than reinstalling the game, try removing half of the objects that you have in your downloads folder. Then see if the game still crashes.

If it does crash, then you know that the problem file is among those left in your downloads folder. If it doesn't crash, then the corrupt object is in the other half of your files. You can keep dividing your files until you find the corrupt object.

Glenda