Windows Server 2008 R2 - Issues

Question

3 major questions, by the way may I say thank you in advance for anyone who takes the time to help out.
Cant get server to recognize additional hard drives
It came factory and I didn't have it setup as a raid or anything they sent me the server with 1 500GB hard drive, however, it has 4 additional slots for hard drives and the sata cables + power for the drives.
Why would'nt I be able to just format the drives pop them in and once the server boots up it recognize them as another drive so I can share those drives out across the network and make them a network share drive?
   2. Cant get DHCP to work.
I setup active directory, DHCP, created a new scope range of 12.0.0.3-12.0.0.25with subnet mask 255.255.255.0. It asked for default gateway of the router which I have disabled DHCP on the router but its 192.168.1.1. I activated this scope.
   3. Does a server have to have 2 network cards in order to hand out DHCP?
I appreciate any responses I am kinda stuck right now and really need to get this finished throughout this week to come.

Answer 1

Thank you very much, ok so here is where im at with the network stuff, havent been able to get the hard drives to work yet, however, you have helped so much so far.
Ok Dave and Peter, its all kinda starting to make sense now to me I believe. So This the setup I have, currently the server is 12.0.0.2 on subnetmask 255.255.255.0 the router is DHCP disabled and has the same subnet mask as recommended above, which finally
made all my PC's running off the NIC's start to work now. I tried changing my router over to an access point and still no internet also my server doesnt have internet, but its handing out DHCP to PC's and they do.... im kinda lost. So looking below at peters
comment and im about to try changing the server scope to be 192.168.1.100-255 to see if that fixes the issue instead of the current 12.0.0.3-25 range. Just wanted to map this out all the way so you guys follow what im doing. I was so excited when i realised
that your recommendation earlier about the subnet mask was what I did wrong, now I have internet on PC's but no internet on wifi or on the server itself.
Ohh wow it wont let me post the picture I have drawn out ok. So
MODEM ------> SWITCH ------> Server (Has no internet Access, but is successfully handing out DHCP)          I made a cross over cable from switch to router (tried this already) and a regular straight through   
PC1(Hard wired to the switch, *Has internet access and automatically pulls DHCP from the server)          
Laptop (Has no internet access connecting to the router via wifi)
Router has DHCP disabled but I tried to turn it into an access point settings and still no internet on laptop
Server its self is handing out DHCP to hard wired PC's and they have internet, however the server itself has no internet access.
We are making progress here i am just probably missing some small details.