Building a Home Server

[pancakelad]

i have two really old computers in my basement and the majority of my house hold runs on macs. so i wanted to turn those two computers into a server with windows so that we can simply connect to the server to run windows easily on ever computer. as far as i know all i need is to fix up the computer into a single ok one and add some software. is there anything else i need to do and will this bog down my already only ehh internet service.

ps. i also plan on making this server into a minecraft server. this is a vey commonly known game and the multi player is based on servers set up by the players so i plan on making one for just me and a few friends so would i be able to use this for both of these purposes?