@havanesefluff The single most important component in determining how well a given computer will run Sims 3 (as with most games) is the graphics card. Although the processor matters too, the GPU will be the limiting factor here. And the Inspiron doesn't have a dedicated card at all. Its integrated chip could certainly run the first few expansions, including Late Night and probably Generations, on lower graphics settings. But if you ever wanted to add a more demanding pack, not just Pets but maybe Seasons, or Island Paradise, or possibly even something in the middle like Supernatural or University Life, the Inspiron might have serious trouble handling it. And if you're planning to keep this laptop for several years, it wouldn't hurt to futureproof for what you might want to do down the road.
The other consideration is the cooling. While modern laptops of any strength should be capable of cooling themselves properly when possible (i.e. if you're not playing in bed with the laptop swaddled in the blankets), models like the Inspiron don't usually have the kind of cooling that would support even moderate gaming. What hardware does when it starts to overheat is it downclocks to lighten the load and reduce temperatures, throttling performance in the process. I don't know how good the Inspiron's cooling is relative to other laptops in its class. But it could easily run hot enough while you're playing that its performance wouldn't even match the best case scenario for its hardware. That's often what happens when people try to play Sims 3 on this kind of laptop, although others manage don't see significant side effects and can still play well on lower settings.
If you had less money to spend, I'd say get a laptop like the Inspiron—the same hardware can cost below $500 from other manufacturers—and see how it goes and which packs you can run reasonably well. But for $900, the G3 is a much better choice. It may last longer too, since you won't be subjecting it to loads it's not designed to handle.
By the way, Late Night isn't exactly corrupted in macOS, it just doesn't install correctly. This isn't a difficult problem to fix, but your new computer will make it a moot point. Besides, the best solution is playing in Windows instead, where all the issues related to trying to play in macOS just disappear.
