My advice? Buy yourself a new machine and reload everything from scratch. RH5 is pretty old. So is that kernel. There are lots of security holes that have been found and patched since RH5 was out.
Depends on what your needs are, but I'd imagine that with your setup, you wouldn't need that much horsepower. I think you could get off pretty cheap buying a new machine. The work is going to be installing everything, but since it's a new box and your existing box is still running, you can take your time about getting it loaded to be sure everything works good.