Well, given the age and your thoughts on doing whatever you can to keep it. I would do an evaluation BEFORE you spend any money by looking at a newer and better OS, preferably free. Linux provides all of that and a lot more but there is a learning curve depending on what you want and what you want to do as the curve gets harder and longer with the "more" you want to do. Some drivers for your hardware may not be free as they are deemed as being 3rd party and not part of the OS itself. Next, survey your hardware within and see what you can upgrade and for how much. Again, do nothing until you have added up the total as it could be more than a newer "used" computer with newer hardware and OS included. Last and least, do not buy a new computer without some serious sole searching as the chip market has gone nuts and prices soared which means anything new and being sold has a sticker price that Ripley's has a hard time believing. Not sure if any of this is worth anything but then good advice is seldom free and the rest comes at your own peril. Good luck and hope you figure out what works for you with the best possible price.