Yogurt is extremely beneficial and nutritious for your body. But you have to look for two things:
1) It has live culture (otherwise it's just a cold custard)
2) It is not bitter or awful pungent (rotten-egg) smell. Just throw away the bad yogurt.
I usually eat 2 to 3 times a week with meal. But just like everything else, consume it in moderation. Milk or any milk base product in extremely excessive amount consume daily (like 2 to 4kg every day) over decades may (not necessarily) give calcium stones.
I prefer unsweetened either desi yogurt or plain Nestle (I don't like flavors but it's my personal choice) yogurt. Both have live cultures.