Wont find anything like SBS (assuming that is what you are talking about) straight out of the box on any Linux distro I know of, if you find out I would love to hear about it. When I looked into it recently the biggest problems were something that resembled AD without having 2-3 (or more) parts cobbled together. I talked with a senior Linux admin and he said that for AD, Linux people just use AD, because there is no other good option out there.
If I was doing something like this I would use Ubuntu server, and then set up a VM with a GUI management suite. I don't remember off the top of my head what the name of the one I used was, but some quick searching has found
Webmin that seems to do the same thing, but through a web interface. Alternately, you could always just install Xwindows on the server box.