Talking to a mates old man, he said to use normal white sugar from the shop, not the coopers brewing sugar and where possible, use glass bottles to bottle it.
thats it, im off to dig up the brew kit........
Loop just beat me to it, and I totally agree with him. Coopers Kits really aren't that great, cos I'm brewing reproductions I'm generally mixing brew kits anyways, so I have used them (though never their yeast as yet). Depending on your brewing method you should still be able to get a good tasting beer out of them. Just make sure you rack your beer to get rid of some of that yeasty home brew taste (with the dead yeast).
For most brewing the best way is to go traditional, try to stick to the German "Reinheitsgebot" law as a base and only use water, barley, and hops; add yeast, wheat malt and cane sugar and you should have all the ingredients you need.
White sugar should definitely be avoided as it's use in commercial beers nowadays is what is destroying the taste of beer in traditional Australian (and overseas) recipes. White sugar is now used commercially as it is cheap and easily available en mass. The problem is white sugar is produced by dissolving raw sugar and purifying it with phosphoric acid. Which is what gives beer (like Tooheys) that sulphur taste and smell (especially when not ice cold).
After moving over to home brew, and non mass produced, preservative free beers (such as those from Steel River) I can't stand the taste of mass produced white sugar based beers.
Anyway something to think about.
Oh and I always use brown glass bottles. You can use clear but the light will kill yeast, fermentation and ultimately your beer. So if you are using clear then keep em covered up. The glass is better as it does not break down and realease chemicals into your beer. And glass is easier to disinfect than plastic, which generally contains pockets of microorganisms (generally increasingly with age).