Hmph. As someone already said, these definitions are highly regional. Here are mine:

• Soda: makes me think of soda bicarbonate, used occasionally in cooking and sometimes in cleaning.
• Pop: Yeah, the drink that comes in a bottle. If it has a cap on it, it goes 'pop' when you open it.
• Soda pop: Somewhat archaic and redundant.
• Soft drink: Any non-alcoholic (ie not hard) drink that's served in a bar; could therefore also include milk, a drink that is not (normally) carbonated (and beer too, I guess, since that's not 'hard liquor' either). A fellow chorus member orders milk when we go to the bar. Really.
• Coke (tm): That's really a specific beverage, like Mountain Dew, Sprite/7-Up, root beer (ugh) and Pepsi.
• Tonic: Mmmmmm .. like some quinine with your gin? This is also a specific beverage. Sometimes called Tonic Water.
• Fizzy Drink: Does 'oo want fizzy drink before bedtime? I think not.
• Carbonated Beverage: On of my university roomates and I would use a phrase like that back in 1978 when we first met. We made everything way longer and more complicated than it had to be -- it was quite hilarious. Graham and I also originated the "NOT!!!" bit that Mike Myers used to great effect in his comedic career. Funny to see it enter maintream culture.