Can you tell us a little more about your party? What type of rides do you like to do? Have you been to any of the parks before?
10/8---arrival time 12:15pm...because of the later arrival due to a flight time change I am thinking DTD for a late lunch, back to All Star Sports and just relaxing by the pool until bedtime...Would you go to Epcot on arrival day instead of DTD?
You don't have a day when Epcot is going to be your primary park, so, yes, I would do that instead of DTD on arrival day.
10/9---MK EMH in the AM thinking of doing Adventureland and Frontier land in the morning, heading back to the hotel for a nap, attend
MNSSHP in the evening and doing Tommorowland and maybe some other rides during the party.
During MNSSHP are you planning on doing any of the party related activities? Such as character meet and greets? Dance Parties? Trick-or-treating? Boo-To-You Parade? HalloWishes? Villains Mix 'n Mingle? I ask because those tend to take up a fair amount of time, which means you really won't have a lot of time to do rides. If you aren't planning on doing any of the party-exclusive activities, then you can probably get in a moderate number of rides.
10/10--- Hollywood Studios day with ADR at Mama Melrose and Fantasmic
I'm kind of ambivalent towards DHS, but I can see how it'd take people a whole day to tour it.
10/11---10:25am at Ohana's....then off to MK for rides we may have missed or just want to do again. OR heading to Epcot
I'd probably aim for an earlier 'Ohana so that you can get to the parks earlier. I would guess that breakfast is going to take about an hour, and allowing for travel and other things, I would guess you won't get into a park until close to noon.
10/12---Animal Kingdom EMH in the AM....leave park around noontime and head back to either Epcot or MK. But want to be at Epcot one night for Illuminations....
AK can be a half day park, if you're not trying to do to many things. Otherwise, it will take more than just a morning to do the rides, see the shows, see the animals, and meet the characters. I highly recommend the Festival of the Lion King show, which requires a fair time commitment.
My general sense of your plan is that you want to get an overview of the parks, without really spending a lot of time in any one location. I don't think you'll "finish" any of the parks given your timeline (and relatively few days), but you can get a sense of what's available in each park. You will have to be very selective in what lines you're willing to wait and how much time you're willing to commit for any one thing.
I think if it was me, I would opt to focus on one park per day. So rather than do mornings in one park and afternoons in another, spend the whole day in the park and then only hop if another park is still open after your primary park closes.
10/8 Arrival and DTD or maybe try for 'Ohana dinner (unless you specifically want breakfast)
10/9 MK and MNSSHP and maybe have a 'Ohana breakfast here (it's pretty easy to get from MK to the Poly)
10/10 DHS (you could hop to Epcot for about an hour after Fantasmic)
10/11 Epcot (open until 10:00 pm) (forgo 'Ohana)
10/12 AK (all day); hop to another park after AK closes (MK is open until 10:00 pm)