I haven't used linspire, but "Live CD's" are just that: You can boot from the CD (Set your BIOS to boot from the CD), and play with linux.
It will be a little slow because it is not using your hard disk, and it will not remember configuration choices between boots, but it will give you a taste of linux, and let you know if your hardware is detected properly.
With some live CD's there's an option to install to your hard disk, you can choose this if you like it. I would recommend you backup your important windows files (if any) in case something goes wrong, or you click the wrong button: This board is full of threads like "Help - How do I get my files back?"
HTH and have fun.