any cereal wont hurt you at all, if you eat it once every 2 days or even once a day, its not like your eating it non stop, but one bowl a day wont hurt you, and there are some foods that do cause breakouts, especially refined sugars, but its alright to eat it the odd time just not all the time, everything in moderation is alright
avoid cereals that have a lot of corn or sugar-things like captain crunch,cookie crisp ,corn flakes. stick to stuff made with bran or is multigrain... u might want to try a cereal with flaxseeds in it as i understang that omega three oils are in it and supposed to be good for skin. other than that...i dont really know. Oatmeal is a nice scrub for your face but you are talking about eating.....
regular cheerios has been great for me. i didn't eat cereal for the longest time because of my skin but i've been eating this for a few months and it hasn't had any negative effect. there's no hydrogenated oils. and sugar is listed as an ingredient but there can't be more than a gram of it in there. nothing flashy, just very simple and a nice snack.
also, there's a cereal called Hi-Lo by Back to Nature with no added sugar and just a little bit of canola oil. it's nice in that it has about 12g of protein per bowl or so. i only find that at trader joe's.
most cereals are high carb so what i pay attention to is the fiber content. if it's high it should offset some of the effects of the carb. also if you like oatmeal get the old fashioned slower cooking one not the instant.