Correct.
As for the hardware you need to run the emulators, that depends on what you want to emulate. The more modern emulators like for PS3, Wii U and Switch you will need quite good hardware.
My general advice would be this, get the best CPU you can with as much hard drive space as you can get. Multicore CPUs generally don't have much benefit in emulation, it's all about the single core clock speed and instructions per clock cycle but they don't make single core CPUs anymore. You don't need a super fancy GPU but you will want a reasonably decent dedicated GPU, a 60 series Nvidia card would be fine without being too much money, a 70, 80 or 90 series card would be overkill. The GPU will help with Launchbox performance and will help if you decide you want to use shaders or uprezzing your games.