You should first determind your IP address subnet ,an example is 195.100.100.0/28 this will give you 14 useable host
on your network address range 195.100.100.1 thur 195.100.100.14, your network is 195.100.100.0 and your broadcast is
195.100.100.15.
Assign IP addresses to your router, switch and server from this range, you mighy reserve the first 4 address for this
purpose and use the remaining for host assigened through DHCP. If you use a routing protocol you must assign the network
address for the portocol to work.you can assign a default gateway for your switch which should be the routerinterface.
CDP is media- and protocol-independent protocol that runs on all Cisco-manufactured equipment including routers, bridges,
access and communication servers, and switches. You can view CDP neighbor but that doesn't mean they are pingable.
Try and go through a simple setup on the router and then the switch after you decied on an IP subnet, configuer
DHCP on the server and exclude the first four address that you will static assign to the network devices. enable a routing
protocol and then display the ip routes. I will send you a link that will tutor you through all of these setup, it is a great learning tool. HTH
http://www.cisco.com/web/learning/le31/le46/products/products-ip-routing.htm