Hear at my university we are getting some Sun Ultra 20 workstations and my boss wants me to make some dual boot Win/Linux (These are AMD machines, I thought they were sparc at first) The question is which Linux distro should I go with that has 64-bit support. He mentioned Fedora because another guy told him about it but my friends in the CS dept have had nothing but trouble with it being unstable.

So I've set my sights on Ubuntu since its based on Debian and I've heard nothing but good things from that end, but I've never really messed with Debian. The point is I want something both stable and easy to admin.

So any ideas for this guy who has been thrown into the job of sysadmin?

Debian is the only choice.
Ubuntu is dumbed down desktop