I'm too young to have seen them all, but The Sandlot is my favourite. And I've seen it many more than 10 times.......when it was released my dad got us the "black box" and I watched it on pay-per-view continuously for about a week until my mom found out that we also got the porn channel
The Sandlot is excellent.
Definitely my most favorite baseball movie, but the best is the Natural. So inspiring.
There are a ton of good baseball flicks:
Field Of Dreams
and I'm not even mentioning the old school movies, ie Pride of the Yankees