Personaly Ubuntu better match my needs. Ubuntu is based off of Debian Linux, and as such, used Debian's APT package management system. Unlike RPM (RedHat/CentOS/Fedora), APT has full dependency tracking and resolution, meaning if you want to install package A, and package A requires in turn packages C and D, it'll install the whole kit and everything for you automatically. This is very nice, especially for beginner admins.

Also, Ubuntu has a bigger userbase and active support forums out of which you'll be able to draw much information (http://ubuntuforums.org). That means more free support. They even have a forum section titled ‘Absolute Beginner Talk’. And like most LINUX distro you can choose between both Ubuntu community support (free) and Ubuntu professional support (cost) from Canonical (http://www.canonical.com). According to ‘Google’s Trends’ Ubuntu is the most active Unix distro: http://www.google.com/trends?q=ubuntu%2C+debian%2C+centos%2C+fedora%2C+slackware&ctab=0&geo=all&date=all&sort=0

Also, Redhat abandoned it's free distribution several years ago (2003) in favor of its for-cost enterprise versions (http://www.linux.com/articles/32467). This is why the included versions of mysql/php/etc are so old. You may have heard of the Fedora Core project - it is basically the continuation of the old free Redhat distro...it has more recent packages available, but still comes with the RPM package management system and all the difficulties it brings along with it for beginner.

Lastly, Ubuntu has frequent updates (twice per year for major releases), and its founder and benefactor Mark Shuttleworth gives freely (http://www.shuttleworthfoundation.org) of his time, money, and energy to a myriad of causes, Ubuntu being one. According to Ken Hess (http://www.daniweb.com/blogs/entry3322.html) Ubuntu employees also appear to be the happiest of any he had meet. They are congenial, inviting, engaging, and are truly excited about what they do.

Be aware that like any newly released software, you may have problems with the latest version (8.10 at this writing). If you're going to use this linode as a production server (serving stuff instead of just playing around), you'll probably want to stick with an LTS release once it's been out there a while.

Read up on it a little bit before you commit a lot of work:
http://en.wikipedia.org/wiki/Ubuntu

Right now, the best release is Hardy Heron, 8.04.1

Of course, linode makes it fun to play with distros, and the newest Ubuntu 8.10 is available. It's just that I'm not crazy about being an early adopter, I'd rather wait and let them work out the bugs.