TLSnell, I take the orders, walk the customers through any questions they have (you'd be shocked how much time this takes), ensure the food is to their liking after its arrived, each course, and make sure I'm available at all times for drinks or anything else they want (You'd also be surprised how many people like to chat with their servers). I think if you went to 10 restaurants with avg checks per person over 25 you might find one where the server routinely ran out food. Usually more junior employees do that until they serve. Its also a method of training I guess. Every restaurant has a team taking care of you, if you can tell it's a team though, they did poorly. That team should have one face, your server, and they should be available when you need them.
Yes, everyone gets a part of the tip from the server to the cooks. As for the Ihop question, I'd put forward that IHOP is a low priced family restaurant and not really in the same category. It is nearly fast food. I eat there a lot, love the pancakes, but it's not intended to be a dining experience. The IHOPs by me all have bussers, which run food too. They are independently owned, so each is different obviously. I have a friend who worked at one for some years and said the money was great, but she also would have 10 - 12 tables at a time. Very high end restaurants cap at 3, most around 5 - 7 with obvious exceptions when servers are missing or its busy, but trust me, the customers know if a server has 11 tables.