No problem about the questions, its what were here for.
Most PSP's are shipping with 2.5 FW, I think. But if you hunted on ebay, or even on here, you can find one with a lower FW. Thats if you want homebrew.
You only need the WiFi Max Adaptor if you want to connect to the internet from your computer, not if your going to steal someone elses. lol.
You can play some downloaded games on 2.0, but if you really want to do that you will need 1.5, i think. But if you DO get 1.5 there will be no web browser so you will have to download a custom one.
If you are going for the movies angle I would get a 2gb memory stick pro duo or duo.
I imagine the Mac doesn't matter, you should still be able to attach the usb cable and connect up the PSP. But you wont get the same variety of converters etc.
Hope this helps
-N