I do not remember when I started timeouts with the kids, my youngest is 7. I would say that you may not want to use the crib for timeouts, even for a short time, because they could associate it with bad behavior. Try a high chair, or even a chair that attaches to a seat, you can usually find one at Salvation army or goodwill stores. As for throwing food and toys, yes Very dangerous. If it's a toy, put it in a bag and tell him something along the way of, the toy can come back out when you calm down, and can play with it correctly. If he throws it again, the toy is gone for the day. As for the food, he won't starve, take it away. Just remember to let your discipline have meaning, be consistent, and make sure that your spouse is on the same page. Your yes should mean yes, and more importantly No is NO, not well maybe just this once, it will confuse him and let him know that there is negotiation room, which there IS NOT.