Have you tried any Linux to this point? Virtually all of the free distros can be downloaded at
www.distrowatch.comeither by http or bittorrent. Just burn the ISO and boot and you are on your way.
Linspire LiveCD can be downloaded free at:
http://media.linspire.com/cnr_linspirelive/The installable version usually costs, but it frequently is offered substantially reduced or free during special promotions. You can periodically google "free linspire" and you might get lucky. Do you have an extra machine or an empty hard drive that needs the experience?
Linspire has more eye candy than most so they recommend an 800 Mhz processor and 256 RAM as minimum. You can do it on less but it is slower, though just as stable. As I mentioned other versions can run on a lot less. As with Windows more can be better, but certainly not necessary.
Of course the Live CD is going to be slower than a hard drive install. You also will not be able to download through click and run to see how easy ijnstalling programs in because you can't install to a spinning CD running your OS. It is pretty sweet. They don't always have cutting edge last second releases, but what they have is stable. You can download with apt-get like any Debian distro, but because it is a specialized install, it could break the Linspire system. As long as you use click and run, the installs go easily, and if a new version of an installed program is available, it can automatically download the updates!
If you have any "exotic" hardware, Linux lags behind onlyh because the manufacturers only provide Windows drivers and then they have to be reverse engineered.
At the very least it would be an interesting experiment. What kind of computer setup do you have?