You get 2 snacks and 2 Quick Service meals a day.
Quick Service meals are basically the same as a fast food restaurant. You order and then pick up the meals at counter. Since you will not have a waiter or waitress there is no need for a tip.
Some of my favorite Quick Service restaurants are:
Magic Kingdom:
Pinocchio's Village Haus
Cosmic Ray's Starlight Cafe
Epcot:
Sunshine Seasons
Hollywood Studios:
ABC commissary
Back Lot Express
Animal Kingdom:
Pizzafari
Yak and Yeti Counter Service
Try
http://allears.net/din/dining.htm for menu's they tell you what they serve so you can look before you book!!!
For snacks you can just stop at any Ice Cream cart throughout the parks, or stop and get a soda or popcorn.