FEDORA BUGZILLA INSTALL
FEDORA BUGZILLA UPGRADE

Ubuntu is a lot more popular with desktop users, while Redhat-based systems are significantly more common on servers. It's all the same software underneath, anyway. Use whichever you're more comfortable with. Ubuntu uses the Debian system, while Fedora uses the Redhat system. In general, Ubuntu and Fedora have more recent packages, but a faster release cycle, while Debian and Redhat (or Centos) have a slower rev cycle but consequently older software. Really, just use the distro you're used to. All of that to say that I'd recommend that you consider installing bugzilla from it's official stable tarball.

FEDORA BUGZILLA UPGRADE

Also, I find that upgrades are generally much easier when applications are installed from tarball, as you can just follow that application's upgrade guide. I find that the packaged versions of applications sometimes put things in odd or unexpected places and as such, you sometimes run up against resistance when trying to get help in that application's support forums, mailing lists, etc.

FEDORA BUGZILLA INSTALL

For applications, I usually install from the official tarball. Speaking personally, I prefer to use the distro's package management for what I call 'base' services - things like apache, mysql, userland tools, libraries, compilers, etc. Contrast that with the most recent tarball releases, which are in the 3.6 release candidate phase.

The current debian stable package for bugzilla is v3.0.4. With regards to Bugzilla, it really depends on how recent a version you need to run.

If you'll be using apache and DAV, then there are a few more bits to configure, all of which are well-documented in various places on the web. If you're going to use svn+ssh, that's really all you'll need. With regards to the ease of installing Bugzilla and Subversion.subversion is easy, of course: $ apt-get install subversion. As such, there's less of a chance that an upgrade will break something. I feel that the Debian package maintainers do a little better job testing/fixing packages before they get promoted to the 'stable' branch. You ought to give Debian a try - Ubuntu was originally based off of Debian and nearly all of the tools (package management, service control, etc) are identical between Ubuntu and Debian, so you'll feel very at home. Ideally, I try and stick with either CentOS or Debian for servers. The Ubuntu LTS version is a decent candidate, though.

I'd recommend you stay away from Fedora for server purposes. At this point, I don't believe Fedora has a server version, though I could be wrong. Since then, Ubuntu has started releasing server distributions as well as its 'LTS' (Long Term Support) server version. Both Ubuntu and Fedora started out as Desktop-centric linux distros.

Fedora bugzilla