Originally Posted by Zyglow
To get you on the right track, Linux is the operating system. The distributions are are collections of software and utilities that work in similar ways.
If you want to get picky about the words, strictly speaking "Linux" is just a kernel, not an OS. Unlike BSD's, which are complete OS's with a proper kernel, a toolchain and some user land tools.
Linux is only the core, and will be of very little use without additional tools.
So, yes, we could say that a distribution conforms a whole OS and add some extra capabilities as well. There are many differences between distros, even if they share the same kernel, even the init system can differ, and the system layout (that includes the file system) is also very different from one to another).
Some people like to call the OS with the string "GNU/Linux", since "Linux" alone is just a kernel, not a proper OS. I'd say that "Linux", indeed, is just a kernel, and each distro is an OS (in fact, nothing forces you to use GNU pieces along with the Linux kernel, you could use whatever you want if you feel brave enough).
But I am sure that this stuff would get pretty boring for the OP if we continue talking about words and useless definitions.
I agree with the poster above, you should try some distros and choose yourself. It's very hard to tell you what is the best distro for you, since we don't know you and we have no clue about your aptitudes and the effort you are willing to put into learning something new.
If you are the kind of person that like things that just works you should check the top list at distrowatch, probably SuSE is a good candidate. Ubuntu is also famous, though I highly dislike it, but that's just me.
If you are brave, you might want to check Arch, or even Gentoo which is what I use. But you are going to have to learn in that case.