Hi Kallison!
I too live in Bucks County. PA and have driven to WDW on several occasions. We break the trip up into two parts. We drive to Hilton Head, SC (where we have family), this takes 12 hours. Then the following day or two we drive onto Orlando, a 5 hour drive from Hilton Head. Therefore, I guess you could say it is a 17 hour drive. My parents have driven straight through and it took them 17 hours.
Any further questions, don't hesitate to ask!