Since I was having problems with my laptop, I thought that I would take steps to back up, slim down, and soup up my old desktop. Partly, I was inspired by trouble4hire, who has been doing this with an old laptop because of problems with her desktop (it's like the laptop/desktop circle of life!) I came up with a list of things to try - defrag, uninstall programs I don't use very much, don't keep a lot of data on the box. mrpet brilliantly suggested that I reinstall Windows once I had backed up everything. He pointed out that the "uninstall" feature for many programs does not work very well and that I might get better results by starting from a truly clean slate. He also suggested keeping it a "clean box" in the future, with a minimum of programs and data kept there, which I think is a good idea.
Since I have tried many, many things to restore this computer to a more workable level of functioning over the past few years, this struck me as a worthy suggestion. I had a backup already on our house server, but that is down at the moment, so I backed up all my files again on a remote server. Right now I am creating a complete backup file to transfer over there, and once that's done I'll be able to start.
Happily, my laptop is still holding on to life. So, I am not as panicked as I might have been. If something goes catastrophically wrong with the install using the Windows installation CDs I saved from my original computer purchase, I can use the laptop to create boot CDs, get help from the Internet, whatever. Hang on, laptop, hang on! Help is on the way!
My two biggest concerns right now are 1) the other hinge will break, meaning I can only use the laptop with a monitor connected and 2) something else will go wrong. One more problem would, I believe, make the computer unusable.
Wish me luck, everyone. The fact that I am even willing to consider undertaking this on my own rather than asking one of my more technically oriented sweeties to do it for me is really a measure of how far I have come in the past few years.