Hello i need some help. I know a good bit about making my computer. I have a power source, CPU, motherboard, hard drive etc. but the only thing i am concernded about is the software i have to install onto the computer when it is built. I do not know what version of Windows to buy! i im looking at Newegg and there are huge ranges of prices so im not 100% sure if i can just go ahead and pop the disk into my new PC and it will load it. Thanks.