We did this with 2 young kids in Nov 2001 and we LOVED not having to drive ourselves around. It really depends on where you are staying. If you are staying offsite, you really should consider getting a car because even the advertised "shuttles" are not reliable.
If you are staying onsite, the Disney transportation will be fine if you have a little patience waiting in line and dealing with crowds. We were pleased with the bus service from the All Star Movies.
Good luck,
Peggy