Don't forget about ports or port forwarding if you're trying to do something fancy and want access from the Internet (serving web pages are you?) - or even access to the internet (have a proxy to consider?).
I like Zoredache's answer. You probably do want to configure your router to reserve a certain IP range so that you can statically assign IP's in one range while allowing DHCP to assign IPs for another (this is not class "segmenting" where you may have to figure out different netmasks for completely separate internal LAN's).
I can only state what I've done for myself where I split my DHCP and static IP ranges by assigning the DHCP range in my class C LAN to start at 192.168.1.100 rather than let it start at the default of 192.168.1.2. That way, I can statically assign IP addresses to devices from 192.168.1.2 to 192.168.1.99. Of course, I could statically assign IP's within my DHCP range too but that may cause problems if DHCP ever wanted to assign an IP that may have already been statically assigned. Of course, I also have to make sure that there are 2 valid DNS addresses either way I go too. And since I don't run my own DNS server I prefer to use OpenDNS with primary set to 126.96.36.199 and secondary at 188.8.131.52 (http://www.opendns.com/). However you can use whatever DNS server(s) you like. Just remember to leave the gateway (192.168.1.1) and netmask (255.255.255.0) alone if you keep it a class C LAN. I only mention this since you may want to do the same.
But if you're using a class B LAN then you probably would want to change your netmask to 255.255.0.0 and your Gateway would then probably be 10.0.1.1. Of course, your DNS would be whatever you like or you could just leave it alone and let your ISP provide DNS services. But as always, you may have to fiddle with ports and firewalls for the really odd ball stuff like VPN or VoIP or whatever. You may have to do it with email services or even HTML too (ports 25, 110 and 80). So don't forget about the ports and firewalls! (...and antivirus.)