I want to know if the box is Fedora Core 4 or Redhat 9, or CentOS, etc... not if it has Kernel 2.6.x
On modern systems you should be able to look in /etc/lsb-release
This should be the LSB mandated way of finding out the distribution across different Linux distributions.
You should not rely on /etc/issue, as it is used for the login message, and someone might change it.
[dummyuser@d400 ~]$ ls -l /etc/system-release
[dummuser@d400 ~]$ cat /etc/system-release
protected by HopelessN00b Feb 28 at 21:45
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