linux_base question

[Chris]

I'm trying to keep all FreeBSD servers in my net as I have since the
late 90s. I have a requirement to get a quickbooks enterprise server
running so I was going to attempt to use compat_linux.

It struck me that if I knew the following list of supported linux
implementations, I should be able to figure out the best port
to use. So far, it doesn't seem too clear to me. Here are the
linux versions supported by the 2 daemons Intuit puts out:

CentOS 5
Debian (Lenny)
Fedora 6 / 7 / 8
Mandriva
OpenSuSE 10.2 / 10.3
Ubuntu 6.06 / 7.04 / 7.10 / 8.0

Here are the components needed.

Gamin - 0.1.7.7 or newer or Fam – 2.7.0 or newer
Glibc – 2.5-3 or newer, or Libc6 – 2.5-3 or newer
Libgcc – 4.2.1 or newer
Libstdc++ - 4.2.1 or newer

Which of the linux_base* ports would be best to
attempt to run these two daemons.

I just updated ports and have the following shown
linux_base-f7
linux_base-f8
linux_base-fc4
linux_base-fc6
(and several Gentoo)

Freshports shows fc4 as what you need to support a 2.4
kernel and the others as "Ignore"? What little I could figure
out suggests at least some of those linux versions above
are 2.6 something kernels. I guessed f8 but then found
threads saying it was experimental. I'm just not getting it.
Is there an easy answer or will this be a trial and error?
I don't know a thing about Linux and never thought I'd
have to.