Hi Tiffani!
Thank you for bringing your question to the Disney Parks Moms Panel!
If you stay at one of the Walt Disney World Resorts during
marathon weekend, there will be complimentary bus transportation for runners and spectators to and from each event, including the Health and Fitness Expo. That is actually a huge benefit to staying on property. Traffic can be a nightmare to drive in on race morning.
Generally, the deadline to register is before it sells out. Most runDisney races will sell out eventually, so I wouldn't wait too long. The marathon stays open much longer than most. You can find registration information on the
Walt Disney World Marathon weekend registration page.
There aren't usually room discounts specifically for runners during this weekend, but I have always been able to find a
Special Offer by Disney that spans that race weekend date. They won't come out until the fall, so I usually go ahead and book a reservation, then watch for the offers. Once the offer comes out, I will apply it to my existing reservation. If my reservation doesn't work with the offer, I'll make a new one and cancel the old. You can call 407-939-4786 for more information and quotes on rooms.
I hope this helps! Please let me know if you have any other questions.