Server backup administration

My network consists of 2x Win2k servers, one runs exchange, the other acts as a fileserver. It’s a single site charity.

Veritas backs up both servers, however in the event of a total disaster, our down time would be too long to re-order a server, re-install programs then install the data and exchange from tape. What’s the most advisable policy with such a small network, including hardware redundancy? Any help/resource suggestions much appreciated..