I'm not an expert on computers in general or Linux in particular, so if I'm vague on something please let me know and I'll try to elaborate.
I have an old computer running Red Hat 5.0. It had a Windows dual-boot (98 or XP - I forget which), but I never used it much and a few years ago when it said it was corrupted I threw up my hands and said good riddance. However, I believe it also had some version of Fedora and maybe something else. I say maybe, because I seem to be locked out of the boot menu.
After it boots up, it hangs for 4 seconds saying something like, "Press any key for options." Ordinarily, I'd be able to press a key and choose my OS. Today, however, I pushed a key and nothing happened. It did its typical sequence 3, 2, 1, then booted normally.
I tried rebooting a couple times, and the same thing happened. My questions are these:
Is there something I've screwed up somewhere that's causing this? Or is it probably just something to do with an ancient machine? Is there some sort of troubleshooting I can do to check for corruption?
Is there a way to restart my computer and boot it from a CD or DVD directly, e.g. terminal command? That's what I was trying to do originally when I found the problem.