Only pictures, video, ringtones, and music can be stored on and accessed from the Media card. (That's why it's called a Media Card.) You can use the media card like a usb disk to store other files with Mass storage mode, but you can't access those files from the blackberry without 3rd party software.
WOW! Not only are you all addicted to your BB, your addicted to this site and forum
So it's like partitioning my PC, I can store all my files, programs, games, etc on the newly created partition but can't actually run my programs/games unless their on the C drive.
Your analogy is correct. Another analogy would be a USB drive. You can store apps on it, but can't execute them from there.
I have a Sandisk 2GB model. It came with 2 adapters, one for use in cameras that use the miniSD format and a full size SD adapter, so you can use the microSD in a computer. Cards are available up to 8GB. How big you need depends on your use.
WOW! Not only are you all addicted to your BB, your addicted to this site and forum
So it's like partitioning my PC, I can store all my files, programs, games, etc on the newly created partition but can't actually run my programs/games unless their on the C drive.