JRE, Java Runtime Environment, and Fedora Core 4 with SELinux don't mix. JRE is version 1.6.0 update 5 and was from Sun Microsystems' web.
I'm just reporting this as info.
Taking up the Java offer to test my installation by following their test link made the browser promptly disappear.
Turning off SELinux's Enforcing is necessary for installing JRE, although the JRE instructions don't say so. (Perhaps a certain SELinux configuration is allowable during the install but I don't know what that is and it probably isn't one of the 2 main defaults.) (Rebooting is not necessary to turn Enforcing off (to Permissive); OK'ing the dialog is enough.) Whether all that means Enforcing has to be kept off to use JRE is something I don't know and I'm unwilling to test it online.
I'm planning to install OpenOffice.org 2.4 without JRE, if I can. If I can't, I'll stay with old OOo (2.0 Beta = 1.9.104) until I decide to upgrade Linux to a distro with a newer OOo included.
Both JRE and FC have been updated: JRE to update 6 and FC as announced.
Why this JRE and this Linux conflicted, I don't know.