1. If you have the dining plan, Can an adult order off the kids menu? And, I guess while I'm asking, are the kids portions really small or somewhat generous?
Most places will allow adults to order off of the children's menu. There were some reports (over a year ago) about a couple of the third party venues not allowing this, but nothing consistent lately. There have been mixed reports about whether or not you can order an adult-sized portion a kids meal at an "adult" price or not.
If you have the
DDP this matters less, but regardless of what is ordered, you will be charged the adult price at buffets (e.g., Chef Mickey), all-you-care-to-eat/family style (e.g., 'Ohana), fixed priced meals (e.g., CRT), dinner shows (e.g., HDDR), and dining packages (e.g., Fantasmic! Dining Package).
2. If you have the dining plan, aren't there certain items you can and can't get?
For the most part, any item in the appropriate category is eligible for the DDP. There are a few places that charge an up-fee for certain items (e.g., Monsieur Paul's prix fixe menu, one of the feasts at Marrekesh). Also, if the item says "for two" then you need two people using the dining plan to order that item. Your server will explain which items are eligible for the DDP, but I can't think of any places that I've been where a specific item was not-eligible for the DDP.
Most of the non-Disney-owned places are very strict about not allowing you to substitute an appetizer for an entree. You also cannot substitute an appetizer for a dessert (Disney-owned and non-Disney-owned venues are both strict about this).
