If one is military, retired or otherwise qualifies the sahdes of green stars and stripes are what we found to be the cheapest tickets. They allow you to go to any park with park hopping on any day of your stay. They also include water parks, pleasure island and disney quest. Check out their website for qualifications and prices. Other then that unless you do a package I’ve never heard of discounts on just tickets unless you are Florida residents or do one of the time share things that are a waste of time.

Dinning options with 5 year olds…Backyard BBQ at Wilderness Campground is a good one.All you can eat with lots of character interaction.
Hoop Dee Doo revue is more adult/older kids but my 6 year old likes it.

pleasure Island is a good spot for adults who like bars/clubs. The adventurers club is a must do if your into comedy skits. They do clean it up if kids are present and kids can go with adults however I would not take my 5/6 year old some jokes are implied and he is now starting to pick things like that up.
Must do attractions if you are staying at a Disney resort I highly reccomend the extra magic hour either in the evening or morning depending on the schedule your hotel could tell you. They have the most popular attractions at the certain park open to resort guest only then. Check out the bottom links for more info on things to do as I could go on forever.
P.S. A good place to meet characters with the kids is at Epcots Character Connection. Check for times!