At a fundamental level all you're doing by creating a program, whether that be a game or an application, is giving the computer a set of instructions. No matter what you choose, you're going to end up learning the basics of computing (how microprocessors work, how memory is stored withing the computer, and most importantly the type of logic and reasoning you need to apply to a problem to solve it). A game design course (to the best of my knowledge) would also have things like level design, character design, modelling, all the things you would need to get into the industry. That being said, there's a lot of cross over between the two, and it depends on what you want to do. If you know game design is something you're interested in than I'd certainly recommend it, but if you're still unsure as to what part of the IT industry you want to go into I would recommend the general computer science course. That being said, I know most uni's in Australia will allow you to switch between courses as long as you do reasonably well at the relevant subjects and you're only swapping withing the same school, so if you change your mind that might always be an option.
