If you start at the road crossing south west of Kent proper (CT 341), you have to climb up and over a nasty piece of trail I have never heard anyone say nice things about. Usually the descent off of St. Johns ledges is described in very colorful terms not suitable for print. However, there is a nice dirt road which follows the river (River road) and goes around this ridge. The road starts by going past the collage campus just outside of town on 341. Starting out with 11 pounds of food on a hot day, you might want to use the River road. You can actually drive up to where the AT crosses.
The best part of that section is right at the CT/MA line which includes Bear Mountain, Sage Ravine and Mount Race. Upper Goose pond is a neat place too. Ending at RT20 in MA (just off the MASS Pike) would be a good ending point. Once past Upper Goose pond, you get into the great swamp and the legendary Mass Mosquitos.
Salisbury is within walking distance of the AT (half mile) and can be used for resupply and a meal. The IGA there is the most expensive in the world, but they sell a reasonably priced made to order deli sandwich. There are even picnic tables behind the store. Hard to say if it's worth the detour on a 5 day trip, but could lower your initial food load.