1.  BULL DURHAM: Clever and hilarious.  Not only the best baseball movie but perhaps the best sports movie of all-time
(Warning: link contains strong language):

2. BAD NEWS BEARS: Just watched this the other night on HBO.  Always takes me back to my Little League days. 

3. MAJOR LEAGUE: Just plain funny.
(Warning: link contains strong language):

4. FIELD OF DREAMS: Just a tad too sappy but obviously a classic.

5. 8 MEN OUT: An underrated but powerful movie.