W2K Server Unattended Reboot?

We are a small office (c. 12 users) with one PC running W2K Server, being used only as a network file server. I have this PC on a UPS as we have frequent power outages for some reason, and some of these are long enough that the UPS battery drains. Problem: I want to keep the file server secure, but I also want it to power back up unattended, if needed after an outage, since I may not be in the office. How do I get by the Ctl|Alt|Del logon process under these conditions and still maintain systemsecurity?