In the 30 yrs we've stayed at most all Disney resorts, unfortunately the bus service from the deluxe resorts seems to be about the worst b/c most resorts share with other resorts. When we stay deluxe we try to stay near the park we'll likely be visiting most. Although we stayed at AKL just once, the buses were excellent. Wondering if perhaps not as good these days now that it will be sharing with the new Villas.
We had very good bus service at FQ, CBR and CSR. CSR bus stops at the parks are the cloest and shortest walk, which is nice and the resort buses are rarely standing room only.
If your mom wants a deluxe resort, then as a pp poster mentioned, the EPCOT resorts have 2 parks within walking or boat distance, then buses to MK and AK. Those buses often share with all the ECPOT resorts, so it can be a long wait - longest wait we've ever had was at BWI.
Happy Planning!!!