Welcome to Flyertalk, Kathleen Brown Heintz!
How many PNRs ("reservation numbers") do you have? If multiple people on one, they should get boarding positions very close together.
If you check in at T-24, you are likely to get a high A or low B. Have multiple windows open and toggle from one to another fast. Check in the teens first if need be for better position. Adults last, as they will be boarding after A60.
Your plan of window/aisle hoping for no one to sit in between is sound.
Don't worry.