Yes, the laptop is 9 years old, the thermal paste probably could use replacing, the fans and/or other internals of the laptop may have copious amounts of dust. I would recommend using the Lenovo Yoga that you have instead of trying to use the 9 year old laptop - just my $.02
Cooling system very likely needs a clean out and new thermal paste wouldn't hurt. That's about as far as I'd go, not worth putting any money into such an old notebook.
I've still got a pre-unibody 15" that still runs, the battery exploded and died years ago back and the fans are on the way out.
A 2011 15" that could boil a water it's still functional but not terribly useful these days, too much heft, and versus too little horsepower.