While the large, mainstream parks are great, and have some world class rides, 2 of my favorite places are right here in Pennsylvania -
Knoebels Amusement resort in Elysburg, PA. This is like a trip back in time for me. Free parking, free admission, reasonable prices rides and food. Not the biggest, fasted rides out there, but they Do have the #1 ranked wooden coaster in the Phoenix, and well deserved. Twister is another great wooden coaster. This is a fantastic family friendly park that won't break the bank.
Kennywood in Pittsburgh is the other. This park is a gem (to me). Many cool new rides. The new coaster Steel Curtain looks amazing. Phantom's revenge is a great one too, just watch that second hill! Along with classics like Racer and Thunderbolt, ad well as the Jackrabbit, and you have a great time just waiting to happen.
Chris