Core parking basically makes your processors go into a sleep state known as (C6) and is supported by most new processors. This allows your computer to save power. There is a trade off for disabling parking. If you use a laptop or tablet, you may notice a slight difference in battery life once you disable core parking on your CPUs. If you disable core parking on your CPUs, your computer may have faster benchmarks. (Reported higher frame rates by gamers and power users).
The Dojo is going down, so I'm still doing my best to grab the most important information off of it before its gone forever.
Here is the original one click tool guide (all images reuploaded to imgur)
Any Edits that I make to the original will be using block quotes so you can easily tell what is different.