90->84->684->287->Tappan Zee->287->GSP->95/NJT, depending on where in Philly you're going
95 to 287 is good, too, I just personally hate 95.
84/Newburgh bridge is a bit out of the way.
I lived in NW CT for 6 years, while my wife's sister lived in King of Prussia. We made that drive many, many times.
Don't forget to get gas in NJ - much cheaper than the surrounding states. Exit 7 off the NJ Turnpike is the easiest place to hit - just follow the ramp that sweeps right for 206 north, and there's a Valero gas station right there at the first light. Easy U-turn, fill up, and you're right back on the highway. As of today, it's 3.43 a gallon for regular unleaded.
Valero 1080 U.S. 206, Bordentown, NJ