Hi,
I'm not nearly as ambitious as you, but I do hop around among 5 locations with LANs. I use NetSwitcher 3.1.8 under W2K Pro on my notebook. Very easy to use. You just set up your network settings for a specific location, crank up NetSwticher, and save that as a named profile. However, it does ask you to reboot between locations. I haven't bothered to ignore it to see what happens. It looks to me like W2K can go between places without any help from third party apps, and without any fiddling or rebooting -- as long as all locations use DHCP. Haven't tried, so don't know for sure.
I hope you post back with your solution, when you find one. I'd be interested.
Regards,
Jim