APPCRASH

@Libersim  The faulting module is MSVCR80.dll, a component of the 2005 VC++ runtime that Sims 3 uses.  This would have needed to be installed correctly in order for you to play, and it's unlikely, but certainly possible, that it has become corrupted.  So you can uninstall and reinstall it if you want.

Hit Windows key-i, select Apps, scroll down to the Microsoft Visual C++ Redistributables, click on the 2005 x86 version (it won't say x86; just ignore the x64 version if it's there), and uninstall.  You can download a fresh copy from Microsoft:

https://www.microsoft.com/en-us/download/details.aspx?id=26347

You only need the x86 version; you can skip the other two.  Restart your computer after installing and before trying to play.

I do think it's more likely that this is a custom content issue though.  The fastest way to find out is to move the Sims 3 folder out of Documents > Electronic Arts and onto your desktop.  This removes all your user content, although the files themselves will still be intact and can be restored later.  Open the launcher to spawn a clean folder, then see whether you can play.  If the game works, the problem is something in your old folder.  If it doesn't, the problem is elsewhere.

If the game runs fine in the new folder, you'll want to test the contents of your old folder to find the problem, since you presumably don't want to start from scratch.  For .package-based custom content, as well as mods, the 50/50 method is the most efficient way of finding bad files:

https://modthesims.info/wiki.php?title=Game_Help:Finding_Problem_Custom_Content#The_50.25_Method

For content installed through the launcher, use Method by Mell on this page:

https://sims3.crinrict.com/en/2011/01/tutorial-how-to-get-rid-of-unwanted-custom-content.html