I have a standalone test 2008r2 server. Totally Stand alone, no internet or routers. It's a DC, and running DHCP that I'll be using to test WDS. However, I think I screwed up on what to assign this test server for IP info. Currently
I have below. But, it won't accept anything I put in for a Default Gateway. I've been putting in, 192.168.1.1, but it won't take. Any suggestions?
IP: 192.168.1.1
SM: 255.255.255.0
DG:
DNS: 127.0.0.1

There is an amazing pack of free network admin tools. click here to download it

You're isolated with no Internet access; you don't require a gateway as that is the IP of your router--which you don't have. Also, I would not assign the IP 192.168.1.1 (since a lot of routers/gateways are sometimes listed as x.x.x.1).
Start at 2. Personally, when I do stuff like this, I start at 10.

There is an amazing pack of free network admin tools. click here to download it

Your default gateway and your IP address can not be the same address. The purpose of a default gateway is so that your computer knows where to send IP packets to when the target IP is located on a remote subnet.
How IP Packets are Routed on a Local Area Network:
Guide | Video
Guides and tutorials, visit
ITGeared.com.

There is an amazing pack of free network admin tools. click here to download it