A useful list of single ‘Live’ CD Linux operating systems. Download and burn one to a CD and use it to boot into Linux on the machine of your choice. No need to hassle around installing Linux or anything tricky like that. A good way to test and compare, and don’t forget that Linux could just give your decrepit old computer a new lease of life!
Although I should say that the Knoppix distro failed to load on either of my two test machines.