Do you have any criteria that you would use to limit movie selections other than age? Do you want to avoid licensed characters or animation? Do you want movies based on books or no movies based on books?
There are a lot of DVD's in that age range but without knowing the criteria you consider important I wouldn't know what to recommend.
My dd likes getting PBS shows on DVD.
You can get lots of nature programs.
We have a similar set up, no "tv," but we have Netflix. My kids favorites are Chitty Chitty Bang Bang and Mary Poppins. I love Mr. Rogers, but the kids aren't crazy about him. Ds (4) also loves Cyberchase (not the greatest), and dd (2) adores Barney :.