IMHO, it will not be safe - as DebbieB posted, there is a 6 lane road to cross. This area is NOT pedestrian friendly. There will be lots of buses and lots of cars driving WDW roads over Easter, and many (if not most) of them will not be expecting pedestrians!
Take the bus. It will be quicker (Disney schedules extra buses when it is busy) and much, much safer for your family.
When you visit at a peak time, you have to expect crowds. We've been at Easter more than once and it is never as bad as you might think from reading these boards. With a little advance planning and a good attitude, you can have a wonderful trip!
Best wishes,
Carol