Well, all copies of OS X will support any localization, as far as I know. If you were to set your first-choice language to Polish, your menus would appear in polish and so on.
As far as how to make the characters, not all of those appear to be available via easy keyboard shortcuts on the US keyboard layout. This is what I would do:
System Prefs -> International -> Input Menu
Select Character palette and/or keyboard viewer from the list.
Select one/both of the polish layouts from the list
Select "Show input menu in menu bar" if it isn't highlighted.
Now you get a flag in the bar. When it's on the Polish flag, you get the polish keyboard layout. You can use the keyboard viewer from that menu to see how to make different characters with the keyboard (i.e. if you open it and press option, you see what you get when you press a key with option). You can also use the palette to insert any character available in any font.