CPL - Allows you to fly and get paid for it. Up to a maximum Maximum Take Off Mass (MTOM) of something like 20,000lbs (or is that kilos?... anyway, nothing all that big and not many passengers)
ATPL - Requires a CPL and IR (both multi engine) and loads of theory. Allows you to fly pretty much anything (once you've got a type rating on that particular aircraft)
Oh, and make sure you know the difference between an ATPL and a frozen ATPL. The flight school will get you the frozen ATPL, then you've got to get 1500hrs (with various requirements like 500 multi crew hours) to get the full ATPL.
With a frozen ATPL you can apply to the airlines.
With a full ATPL you can be captain of an airline.
As a sweeping generalization. The biggest thing you'll fly with a CPL is a King Air. If you've got an ATPL, then you can fly anything.
Turbans? Yes, airlines like 500 hours "turban" experience
Sorry, too easy!
In an interview you'll be judged very quickly on appearance. I'm sure you know better than me how a turban can be judged. Some will instantly (maybe subconsciously) reject you. But I think that generally if you look professional, it shouldn't be an issue.