Workgroup/Domain

I have a small business with 16 users and 1 Win2K server and a new 2003 server that is not yet installed. We are currently set up as a workgroup and am considering switching to a domain. Is this worth the effort? We have 1 IT person(me) and a small budget. What is the best way to get started? Internal security is not that big of concern but centralized backups and not having to go around to 16 desktops would be huge. Just looking for help in how to get started.

Thanks.