bstephensonn Your dxdiag lists a few crashes of the graphics driver, and given your other symptoms, that's the obvious place to start. (The Sims 4 errors in your dxdiag are somewhat generic but can be caused by a bad graphics driver too.) So please do a clean uninstall and reinstall of the driver, as described here:
https://crinrict.com/blog/2019/02/clean-re-install-of-graphics-drivers-with-display-driver-uninstaller-ddu.html
Please let me know what happens if you try to start a new save after reinstalling the driver. If everything works fine, you can try one of your main saves too, but no mods or custom content yet.
