Hi Holly!
The transportation between different parks will usually be by the Disney buses. Ideally, you could be between all of them in less than an hour.
Go to the
Walt Disney World Marathon website, click on "RUNNER INFO" and then download the "Official Race Instructions". If you go to page 61 in that booklet, there is a great list of all viewing points for both races, how you travel to them, and what mile they are located. This is a great resource for planning out your viewing points.
If it were me, I would pick about 4 points spread out along the course to see him. Also, be sure to sign up for "runner tracking". You can find this on the website. It is under the "SPECTATORS" tab, and then "Runner Tracking". It will become active soon. This will alert you with text messages when he crosses certain points of the race and give you his pace and estimated finish time.
Please let me know if you have any other questions!! Tell your husband "Good Luck"!