I'd say the full fat and also lean toward Brown Cow yogurts (you can find at natural food stores.) One thing to watch for in the standard brands (yoplait, etc...) is nutrasweet or other artificial sweetners. Also the addition of refined sugars.
You might use plain yogurt sweetened with pure mape syrup or honey (it takes just a touch.) and your own fruit additions.
I really like the Brown Cow because it's made with real whole milk that's not full of hormones and crap, but before I found it Yoplait was the only brand that seemed to be available without the artificial sweetners.
Sorry, this doesn't seem to make too much sense but the kiddos are clammering to get outside.
hth a little