Can I ask why you want Linux. (class purposes, personal purposes, experiment etc.. )
Have you ever used these OS'?
If not the more logical way is to install them on a virtual PC. This way if you're not satisfied they're a lot easier to get off your PC. You can install Virtual PC 2007 from Microsoft (for free) and then simply put the disc in and create your Virtual Machine and it will bring up the OS in a new window. It's like having to PC's sharing one screen. I am unure if you've looked into this at all but it seems more logical for someone who has never used it before!
This first link is the download!
Download details: Virtual PC 2007
This second is the how-to!
How to Use Microsoft Virtual PC - wikiHow
Let me know if this seems like the right path or if you'd rather do a dual-boot!
Rick