carbs and sugar in certain foods

I was just wondering what peoples opinions were on the carbs and sugar in things such as milk, natural yogurt and fruit.
Are the sugars in these as bad for u as other sugars such as those in say sweets (I'm not talking about their nutrition in general, I know sweets aren't good for you, I'm just using them as an example of sugar in other foods). I'm really trying hard to eat better and on a typical working day I will have milk (with cereal) before going to work and have about 250ml of natural yogurt with strawberries as part of my lunch on my break. Obviously these are bulking out my sugar and carbs intake and just wanting other peoples opinion on whether it's wise to cut these out or not to worry about these as the sugars in dairy and fruit are naturally occuring sugars?
Thanks in advance for your opinions