Hi Heather!
I think this is great! My husband and I LOVE our runDisney, adults-only vacations. In fact, I wrote a post about it for the
runDisney blog not long ago. In it are some tips of fun things we like to do when we are there without our boys!
As for resorts, they are all great choices. During marathon weekend, all of the Disney Resorts will have bus transportation to and from all of the race weekend events. This is a huge benefit for staying on Disney property.
If I had to choose one, I really like Port Orleans Riverside. My friend and fellow panelist, Jodie, describes it best. She loves the relaxed and beautiful atmosphere, and the food court is great!
If I could recommend a dining place for you, we love to eat at
Narcoossee's when it's just the two of us. It's located at the Grand Floridian Resort, so you wouldn't need a theme park ticket. It would give you a great excuse to take the bus to the Magic Kingdom and ride the monorail to Grand Floridian. A Disney trip just isn't complete without a zip around in the monorail:)
I hope this helps! Please let me know if you have any other questions.