If you're in a Craigslist city you might offer someone a twenty to take a stab at it, instead of just throwing the install CD at it.
Try holding down the F8 key right after you turn on the power, to get into "safe mode". It might be able to recover without you building the box over again from scratch. WATCH THE SCREEN, don't just flip the switch and go do something else while you wait for it to crash. You might see something that would help fix it.
If not, then you boot off the CD. (If it doesn't boot off the CD, there's a keystroke, usually "Delete" or "F1" that you hit right at boot up that gets into the setup screen so you can make it look for the CD-ROM first instead of the hard disk.)
Once you boot off the CD it might offer to "repair your existing install." Try that.
If THAT doesn't work, you boot off the CD (again) but do a fresh install, one that wipes off the hard disk. That sucks because you also have to reinstall all your software and all your porn^W documents... and that's assuming you have backups of those.
Having three boxes all go Tango Uniform like that at the same time, it sounds like a virus, or maybe one of the kids screwing around. Might want to keep an eye on the little darlings once you get things working again.