I asked you more questions than you answered w/o details. If you are unable to answer w/o reason then I am not able to help you. If you are unable to answer because you can not perform some commands try running them from your installation CD (you can use it as a Live CD) or run any other Live CD.
And please give a compelling reason why you can not upgrade or install an OS. Fedora Core 5 is old, deprecated and no longer maintained. This means you miss out on all the important (security) improvements and fixes.
Next to Glibc problems (while you have not shown any proof for it) segfaulting could be due to a compromise. As a hedge I will post the Intruder Detection Checklist (CERT):
http://www.cert.org/tech_tips/intrud...checklist.html in case you want to try that approach.
Whatever you do you will have to post less terse to provide us with things we could help you with.