Ok here are some thoughts on this:
1) The cost of a 7 day base ticket is $394.05 (and can be found at a discounted price of $382.20) so I'm going to rule the upgrade to AP option out since that costs more. Also if you go with the SPD discount you all have to have the same ticket options so the AP upgrade isn't an option in that scenario.
2) I'm going to look at just your Jan 1 - Jan 7 stay portion - obviously you can book a room for 12/30 & 12/31 at the same rate in either instance. I would book 12/31 & 12/31 through a discounted site like
Undercover Tourist/Orbitz/Cheaptickets to save something on those nights. I'm assuming your stay is at All Star Music in both instances to make for easy comparisons. If you're looking for the least expensive option it does not make sense to stay at a moderate resort (even though it includes the full dining plan) because the addition room cost offsets any dining savings.
3) Here's how the SPD components work for you:
Room = $805.69 (reg. price)
Tickets = $1,182.15 (reg. price)
Disney Pkg Adjustment = $4.19
(for some reason when you book a package with Disney it costs approx. $1.40 more per person than buying room & tickets separately - I know that's strange!)
QS Dining Plan = $500.40 (discounted by 40% - this is the only thing discounted in SPD package)
Upgrade to Reg Dining Plan = $377.82
TOTAL SPD PACKAGE PRICE = $2,870.25
3) Here's how room only discount would work for you:
Room = $707.03 (discounted) - You SAVE $98.66 vs. SPD (you could potentially save even more here by booking through Undercover Tourist (5% discount) or Orbitz/CheapTickets (which may offer a 10-15% discount) and those discounts stack on top of the Disney discount. So you could save another $35 - $105 there.
Tickets = $1,146.60
(discounted through Undercover Tourist - Mousesavers link, FYI you need to sign up for the newsletter to get this) You SAVE $35.55 vs. SPD Ticket cost
Dining = I'm not sure - you'd have to figure out what your dining cost would be for those 6 nights/7days vs. the dining plan above.
TOTAL PRICE WITHOUT DINING = $1,853.63
SO MY ULTIMATE CONCLUSION - if you can dine for those 6 nights/7 days for less than $1,016.62 the Room Only may be for you - also those additional discounts with Undercover Tourist/Orbitz/Cheaptickets could come into play and make that number even larger. Let me know what you think or any additional questions.