Question : change DHCP Scope

I need to change the DHCP scope. DHCP is being controlled by my firewall.
 I want it to start at 10.1.1.21 and go to 10.1.1.1.254.  
I have 45 workstations and printers running on the network now.
 If I make the change to the scope and one of the machines currently has an address that will be in the reserved scope what will happen?
 Would it be better to shut down all workstations and printers first?
 What happens when a machine comes back up and wants an address of 10.1.1.15?  
Will it get a new one within the new scope.  
All servers are static.  Servers are 2000 and 2003.  1 Exchange server.  Workstations are 2000.  One user has XP.  Thanks
cja131

Answer : change DHCP Scope

it should get a new one between the range and since its in the same subnet, you should be able to connect and everything should be fine... ofcourse there will be some which may need to be done manually
ipconfig/release
ipconfig/renew

for printers.. too try to reset them manually if restarting does not pick up the ip, it should theoritically..