We took my son when he was just a little over 13 months old. He is a big boy and has a big appetite so most places we got him his own meal. That is how it worked at home when we ate out too. Sometimes he ate the whole thing like a starved animal (I'm looking at you, Be Our Guest meatloaf kids meal) and sometimes he barely touched it (Le Cellier...).
I echo the comments about buffets/family style. I also strongly echo the disposable placement comment - those plus disposable bibs were so easy and kept meals much more manageable. Kids are still a real mess maker at that age.
I add a tip to get a "leash" for whatever sippy cup you're using at the time (see my profile pic). Major lifesaver. If he wasn't deliberately throwing things he was knocking it over. We attached to stroller strap, high chair, and even our wrists at times. Can also use for toys. Ground and even restaurant floors are not exactly crystal clean.
One more tip - bring both regular wipes and some sort of hand sanitizer/antibacterial wipes/something strong for when you haven't recently washed hands and its food time.
Another thing not quite mealtime related but still...we were planning to quit the pacifier cold turkey at 12 months like we did with his sister, but instead extended it through the trip. This was a big headache saver too - not only on the plane, but also in shows and just whenever he would get overwhelmed (Disney can be really overwhelming!). The day we got home we put them all away and he wasn't too fussy. They can be pretty chatty and it was nice to be able to keep him quiet when he started fussing in shows like Nemo or whatever.
He was already on milk and we were in a 2BR in BLT with a kitchen so we had garden grocer deliver whole milk and cereal and hot dogs and such. We didnt find anywhere that had whole milk, so when out it was mostly 2%. I knew he would at least get his whole milk in the AM, after his nap, and before bed...and we could do a quick dinner if needed. (This worked well for his 4 yr old sister too). We also had snacks delivered - things he really liked at home that were easy to carry (for him, goldfish, granola bars, and applesauce pouches). I brought and used at least one or two each morning in the park. (Most days we had cereal in the room, hit rope drop and toured, had a TS lunch around noon, and then hotel & nap, then back to the parks from about 4-7).
Although the trip was timed primarily for his sister, he did have a LOT of fun. I definitely have some great memories of things he did. He really liked: Any playground, Small World, the Tiki Room, and any show with live music. He even kept his 3D glasses on for almost the entire Muppets show. So cute! Have fun!!
