Carla Schroder have a look at Ubuntu Server Edition to see if it lives up to the hype.
It's posted at enterprisenetworkingplanet:
Do You Trust Ubuntu On Your Servers?
This is a good question. Ubuntu uses up-to-date packages, instead of moldy old goo like Debian Stable or Red Hat Enterprise Linux. Presumably this incurs increased security and stability risks. I have no problem with recommending it for LAN servers and low- to -medium important Internet-facing servers. Pay attention to your border and application security, and keep your systems updated as wise admins always do. Most importantly, remember that ease-of-use does not mean it's OK to be ignorant.