I’ve Finally Decided To Play Around With Linux And Other Opensource Software. What Do You Recommend?

The latest Ubuntu distro is NICE! And take up PHP as there is many “free” opensource choices there also.

That depends on how you want to “play around” Ubuntu Linux is a Debian derived distribution that is currently very popular, as is Fedora. Most “distributions” contain very similar software, they just come pre-configured in various ways (such as for a “Desktop” or a “Server”).
If you want to get more “under the hood”, then take a look at a “vanilla” Debian install, or Slackware.
Whichever distro you chose, it’ll come packed with great, free, open source software. The world is your oyster… welcome to freedom!