it depends...
if you have a decent modchip like the DMS4 or the matrix or crystal chip
then you wont need to do anything and will be able to play the game on your PS2. if you have the swap magic then youll have to do some messing around with the game to ensure itll work, maybe someone else can help you on the swap magic topic.
hope this helps mate.
just burn it and try it. if it works, but your screen is fuzzy and bouncing up and down, then u have to change the GhZ or Mhz (i forgot which one it is). there should be a language select screen first, followed by a screen to change the Mhz/Ghz. different games have different menus. For me, on the language screen, it is usually always highlighted for english so just click X. on the Mhz screen, try and look through the fuzz. Pick the NTSC seeting, or 60Mhz. It should work fine, as it does for me. its just figuring out what to click through the fuzz thats the hard part.
Joebeezee, if you have Swap Magic, you can most definately play PAL games on a NTSC tv and playstation. I download PAL games all thew time, and they work great.
But you have to reply and answer Dan's question of how do you play your back up copies.
Yes, with Swap Magic you can change screen modes and play them.
But you will have a small peice of screen cut off.
That is if your TV can support both formats, if not then you will need something a lot more expensive like a converter.