Switching static to DHCP

[Ashley M. Kirchner]

    I'm looking to switch our current, static, network to a DHCP one.  
There are several devices on the network that would need to remain 
static, but for the most part I can switch all the client computers to 
DHCP.  So, the question is, if I configure a DHCP server on the network, 
define all the MAC addresses that need to retain their current IPs, and 
then little by little start converting all the client machines to DHCP, 
will there be any problems with those that haven't been switched over 
yet?  In other words, will the network continue to function with some 
machines being static and some having been switched to DHCP?

    And a related question, how do I define something like, say a set of 
MAC addresses to have only a certain range of IPs?  Out network is 
broken down into IP ranges.  .100 to .120 is the management range, .50 
to .60 is shipping department, .80 - .90 is sales, etc., etc.  So 
ideally I would like the DHCP server to also behave in that manner if it 
encounters a request coming from a particular MAC.  If it belongs to a 
particular group, then only hand out IPs from a specific range.

    Thanks