If you are thinking about installing Linux on your hard drive, I highly recommend making a dual-boot system where you have both Linux and Windows on the hard drive and can choose between them when you boot the computer.
Making a dual-boot system involves these steps:
Remember to backup your data before trying any of these steps, and perform this installation at your own risk. (I have done it many times myself, with great results.)
If you have any questions, post them here.