I'm going to take a stab at it, but please don't hate me if I'm completely wrong. I'm giving you the calculation on a per night basis, as I'm not sure how long you're staying. I think I understand the deals...but I've been wrong in the past.
There are two possible deals: For the room-only discount you save 30% off room-only rate at POR (about $60/night for late January).
For the "kids of all ages" deal you will save $153 per night (if you want the standard dining plan) plus some savings on the park tickets (that depends on # of days). Here's my reasoning, if anyone wants to pick it apart. You'll be able to add standard dining for all 5 of you at the kid rate--instead of paying $55.59 per night for each of you who are ages 10 and up, you'll pay the kid rate of $17.16 per night for each of the 5 in your group. If you get the standard dining plan that saves you $153 per night of dining (because 4 of you eat at the child price) over the regular dining plan price. Since you don't currently have dining it will add money to your plan, (cost of $85.80 to feed all 5 of you per night), but if you were planning to eat 1 quick service and 1 table service and 1 snack per day then this is a better deal for you than the room-only discount. (If you don't have your ADRs then you will want to jump on that to get the table service meals you want on this plan.) You will save an additional amount of money for the park tickets--but it depends on how many nights you're staying.
For my family of 5 with 4 "adults" we'll save $72 total on the park tickets for 5 day tickets. We're staying 4 nights and have 5-day tickets and we'll save $684 total between the food "deal" and the ticket "deal". It's not as much as I was hoping, but it's better than nothing! Of course, I am Disney-visa-less, so I will be anxiously watching for the update next Wednesday!