@jessmorrow I'm not sure what you're asking. There's no reason you need to uninstall the game itself, and uninstalling and reinstalling the graphics card driver wouldn't touch Sims 4's program files or your saved game data. Can you play a new save in the new Sims 4 folder? If the game runs well with a new Sims 4 user data folder in place (the one in Documents\Electronic Arts) now, then you can skip the uninstall and reinstall of the graphics driver for now. I thought the game was still crashing, which is why I suggested replacing the driver.
Your save files are normally located in Documents\Electronic Arts\The Sims 4\saves. When you moved your Sims 4 folder, you moved your existing saves along with it. But you can put them back and test now that the new folder works. It's a good idea to copy each save file, rather than dragging and dropping it—that way, you have a backup copy if you need it. You can right-click on any of the saves and select Copy, then right-click in the saves folder inside your new Sims 4 folder and select Paste.
If the new saves work but the old ones don't, try loading an old save and playing with a different household instead. You'd only need to do this for a few sim-hours, then you could save, quit, reload, and go back to your old family.
If any of this doesn't work, please describe exactly what happens, and what you're trying to do when it happens. Please also let me know whether you're using a new save or an old one.