DS is almost 16 months, so we're still exploring all the foods that are out there, rather than banning much, but for now:
NO artificial sweeteners (this is a biggie for me!)
NO peanuts (I have excema, which apparently ups his likelihood of an allergy, so we're going on the safe side till at least 3, if at all possible)
NO candy/gum/popcorn/other unnecessary choking hazards/treats
In general we try to offer organic foods, lower-processed foods, whole grains instead of processed, steamed instead of fried, etc. But yes, he's had fish sticks at home, a few chicken nuggets from Wendys (MUCH better than McD's!), and at least a handful of ice cream tastes... but those are few and far between, and we're mindful of buying less-chemical-ridden ice cream, better quality fish sticks, etc.
I am becoming more aware of HFCS in products and am trying to cut down on it, and because of my high blood pressure, we've always been aware of sodium counts, which we're watching with his food as well - it's amazing how much sodium they put in some kid's foods! That said, we do have some of those evil little Gerber Graduates meals on hand for those times when we just do. not. know. what to feed him, or when we're out and about and he's gotta eat RIGHT NOW... again, it's an occasional solution, not an everday thing...
In the future, I'm not sure how vigilant I can afford to be about juice and other issues at daycare, as I can not really afford the "better" daycares that cater to each parent's dietary concerns... that said, I'll do my best to send him with yummy stuff that wouldn't make my stomach turn for him to eat, and just hope he sticks to his lunchbag instead of what they offer.
As for the vegetarians who don't want to "inflict" meat-eating on their children, saying it's a choice they should make on their own, it's sort of funny, because as a meat-eater myself, I would not "inflict" the choice of vegetarianism on my kid until he was old enough to choose it for himself! This is NOT a dig - I actually really respect vegetarians for the most part - I just think it's sort of funny how our beliefs/positions shape our perspectives on choices like that...