I don't think you quite understand. Linux and OS X are operating systems, like Windows. They don't run on Windows, they replace it. Linux will easily work on most hardware, even old stuff.
Luckily though, a lot of Linux distros come with a "Live CD" or "Live DVD", which means you put the CD/DVD into your disc drive, and then change the boot sequence so that your computer boots off the CD/DVD instead of the hard drive. You can then play around with Linux without installing it over Windows.
Luckily though, a lot of Linux distros come with a "Live CD" or "Live DVD", which means you put the CD/DVD into your disc drive, and then change the boot sequence so that your computer boots off the CD/DVD instead of the hard drive. You can then play around with Linux without installing it over Windows.
