First thing you need to do is get your OS backed up. Use the manufacturer's utility to make a Restore Disc. Whether you venture into the world of Linux or not one day you will most likely need that disc (hard drive goes bad, OS blows up, etc) and if you don't have that Restore Disc you may find yourself paying dearly (in both money & time) for something a few minutes now would have avoided.
Second, two words: Virtual Machine! You may hate Linux. Some people love it, but some people hate it as well. If you set it up in a virtual machine first if you don't like it you can just delete a few directories & go about your business. If you do love it then you can think about blowing away hard drive and installing Linux full-time.
Third, another word: multi-boot! Don't forget the ability to multi-boot. You could shrink your Windows 7 partition, install Linux on another partition & switch between OSes at will having all the advantages of both at your disposal just a reboot away.