Okay, one more question, to get the MAC address, do I have to connect to the internet, because my router is set to WPA, and my DS Lite doesn't support that.It's all confusing at first, so take it in stages. Stage 1 is finding your parameters. Here's a good video explaining how to do that on a Mac.
Try it, it's only the way, as my son says.
RNG Abuse Using PPRNG--DS Game Configuration/Parameters Searcher
Note you cannot use this method on a DSi or 3DS, and you should reach Victory Road first so you have reasonably high level pokemon to catch.
Also note, when it asks for your MAC address, this is the address of your DS, and has nothing to do with your computer.