It's not only for laptop. Desktops can overheat if they don't have proper cooling or the computer has allot of dust blocking air flow. No matter what you have laptop or desktop, they can overheat which can case permanent damage to computer hardware.
the i7 is better than the i5. the sims 4 is processor heavy so the i5 would be more beneficial for that game. The sims 3 would be fine with the newer i7 and is not as processor heavy as the sims 4.
the the LED screen is better than the LCD screen