MoBo = Motherboard
I'll bet the CD you have is the one with the drivers on it for your motherboard. If you have another working computer, you can put it in the CD drive and browse through it. If it tries to auto-launch on that system and says it's the wrong hardware, then you should be good-to-go on the system you just bought. When windows is installed, it will have very basic, generic drivers so you can use the basic hardware (mouse, keyboard, monitor), so even if you don't have the specific drivers available, you can still use a basic OS. The driver CD that comes with the motherboard will have all the USB 2.0, chipset, LAN, etc.
Regarding torrents, I can't help you with that one, I'm afraid.