I recently started a thread about getting started in programming a multiplayer game. I've done some reading for programming Flash Actionscripts to do internet database changes. I've read alot about PHP and ASP, etc... but I still really don't know what would be best for me to spend my time learning. I can't learn them all and each one seems like it may work but I am not sure... Basically this will be a turn-based game so it won't require fast updates, even if the updates are just once per second that would be more than enough. The update information doesn't need to be fancy, simple text will be sufficient and then I can break it apart within the program. My question is, given the situation above, what would be the best method for me to create my games multiplayer aspect so that information is updated properly and I don't end up with a bunch of internet security issues...

I would suggest just picking one and running with it. It's cheap and easy to get started with PHP, so I would start there. Then try to develop what you need. I would start small, and get something like a Tic-Tac-Toe working right first. If you're just learning, you'll have to write a bunch of code before you get it working right, and after that, you'll have to write a number of games (and ideally read the code for other written games) before you're actually really good at it.