I have been to, Wrigley Field, Old Comiskey, Old Tiger Stadium, Old Yankee Stadium, Camden Yards, Fulton County Stadium, Turner Field, Skydome, Candlestick, Oakland A's, King Dome , Olympic Stadium - Montreal, Minute Maid in Houston, PNC Pittsburgh, Nationals, Citizens Bank Philadelphia.
Favorite - PNC Pittsburgh, for the views, and the park itself.
I also like Nationals Park, Camden Yards, and Turner Field. Turner is a long walk from downtown, but a lot of kids activities.
Ones I want to get to: StL, Cincy, Cleveland, SF new, SD, Colo, New Tiger Stadium