I now have my two desktops configured on fixed IP addresses .100 and .101. DHCP is enabled with an IP pool range of .102 to .199 for anything else we occasionally connect to the network. (Laptops, XBOX, PS2)
It was a lot easier then I thought it was going to be, I have rebooted the router several times and it appears to be working.
I haven't had SCSF's problem because my router always assigns the same IP to a computer anyway. I only had to force the fixed address when I replaced the network card and the router thought it was a new computer.
FWIW, I've also learned I can do he same with Comcast for the IP they assign me, which is normally always the same. If I ever need a new IP address for some reason, all I have to do is program my router for a new MAC address and Comcast assigns a new IP. However, if the modem MAC address changes, I have to call their office to get it recognized, but not for a router change.