Also take a look at
distrowatch, which contains the multitude of Linux, BSD, and *nix variants that are available. This might also confuse you a little as there are so many ...
The word these days is the
Ubuntu distribution is great for new users, as it is highly stable and easy to use.
The
Gentoo dist., as well as being pretty stable, has a very large user support forum, 100,000+ registered users, that can help you with most any problem you might have(it helps to have PIII equivalent or better hardware with gentoo, as you will compile most all your packages, apps, as you will likely be running X).
You can also try the
Live CD's of any particular distro to get a feel for their interaction. (livecd is a bootable cd that takes you to that distro environment, without installing anything)
Hope this helps ...
/biased gentoo user