You think you will never need to deal with such an old thing like Windows 2000 computers because we are already in 2011. But in reality, you may still have to without many choices. For example, I just recently had to move 2 ancient Windows 2000 machines to vSphere server. Not as easy as you do it on any recent version of operating systems.
1st, service pack 4 needs to be installed on these Windows 2000 machines.
2nd, this update rollup needs to be installed on these windows 2000 sp4 machines.
3rd, use VMware vCenter Converter 3.0.3 on the local machine to do the P-2-V.
Lastly, the steps described above works for both Professional and Server editions. Hope you don’t have to deal with it in any chances but if you do I wish this post can help you out a little bit.