These are the current allotments on the regular (basic) dining plan (1 TS, 1 CS, 1 snack per night)
TS at breakfast/adult: One entree or combo platter, one beverage. No dessert and, in 2011, no extra beverage in lieu of dessert. Separate side dishes not included.
TS at breakfast/child: One children's menu meal, usually consisting of an entree, possibly a side, and a beverage.
TS at lunch/dinner for adults: One entree, one dessert, one beverage. Separate side dishes are not included.
TS at lunch/dinner for children: One children's menu meal, usually consisting of a small appetizer (raw vegetables or a cup of chicken soup), one entree, and one dessert.
CS at breakfast/adult: One entree or combo meal, one beverage. No dessert. Separate side dishes are extra.
CS at breakfast/child: One children's menu meal. If the restaurant has no children's menu, a child can order anything off the regular menu.
CS at lunch or dinner/adults: One entree or combo meal, one dessert, one beverage. Separate sides not included.
CS at lunch or dinner/children: Children's menus at Disney CS are set up where the child can choose an entree, then pick two items from a selection of "sides." However, one of these sides counts as dessert. If the child wants a dessert item they need to pick one as one of their two "sides." The kids meal also includes a beverage. If the restaurant has no children's menu they can order an entree, dessert and beverage from the regular menu.
You can eat at any resort, not just the one you are staying in.
At buffets and all you can eat family style restaurants, the full buffet or full menu, plus beverage, are included in the table service allotment.
If you are on the deluxe plan the allotments for a la carte restaurants will be somewhat different.