My recommendation rent a car, stay in Anaheim. Consider Magic Mountain rather than Disneyland. If you do stay in Anaheim find a hotel that has passes that allow you to and come go into Disneyland. You have a short amount of time don't waste it using local transportation. No one buses in LA anyway..
If you don't mind a bit of a detour
go along the central coast through
Big Sur along the 101 until you get to either
Carmel or
Monterey . The
Hearst Castle is also a treat to see. So many things so little time... You could make a quick detour into the castle which is on the 1 near San Simeon before heading up to Big Sur/Monterey.
Write back if you have more questions.