First thing what do you mean from scratch? If you mean building a computer to run the server it would depend on how many people are going to be on it at any given time i myself have a 3.2 p4 single core with 2g of ram holding 5 people with no problems but that is the limit for more i am build a quad core 2.8 with 6g of ram should hold a good bit of people. But if i am just spinning my tires and all you need is a start then i would use Galactic Cataclsym 4.1.0 repack & +4.0.6 repack

it seems to be the easiest one to set up and if you have anymore ? i would love to help as much as i can