@ManeEvent4U2 There is one setting that stands out—your screen size. Your monitor's native resolution is 1280 x 1024, which is a 5:4 ratio, but you're using a 4:3 ratio instead. Having an aspect ratio that's not supported by your display can indeed cause the lagging you've described, although why your sister isn't seeing the same problems is an open question. Anyway, using a supported resolution should help.
Are you saying that if you pull your existing TS3 folder out of Documents and try to launch the game, you're getting an error message that you need to have Origin installed? (You'd be doing me a huge favor if you described exactly what you see in as much detail as possible; it might matter to a completely different TS3 issue that we've been trying to troubleshoot all weekend.) That's not normal and not the way these things are supposed to work—the game folders were designed to be swapped and refreshed just like this.
In any event, the following files can and should be deleted from your game folder often, or even after every play session if you remember. Most of them will regenerate each time you launch the game.
- The five cache files directly inside the game folder (CASPartCache, compositorCache, scriptCache, simCompositorCache, socialCache; if you see extensions in File explorer, they'll all end with .package)
- Everything in FeaturedItems—this is the game trying to sell you store stuff while you play
- Everything in DCBackup except ccmerged.package. Don't delete ccmerged, as it's critical for your premium store content
- Any files in CurrentGame—this should always be empty when you're not playing
You can help your game by moving Screenshots and Recorded Videos, if you use them, elsewhere on your hard drive. You should also store the files in Downloads elsewhere after you've installed them, but it's a good idea to keep these as a backup, in case you need to reinstall later. Crinrict wrote a guide to your user files, if you're curious:
https://sims3.crinrict.com/en/2011/01/faq-user-files.html