I like Thom's route except the I-88 part. It's being worked on, but it is a miserable road.
Instead, I would pick up I-84 off I-90/Mass Pike in Sturbridge MA to I-81 in Scranton PA, or cut a corner and do I-84 to US209 down the Delaware Water Gap to I-80 to I-81 in Harrisburg PA.
Be aware that I-81 does traverse some mountainous terrain and you should watch the weather and be prepared to go east of the Appalachians. You could take I-81 to US50 and US17 to hook up to I-95 north of Fredricksburg VA and miss all the DC/Baltimore mess. You can grab I-20 through Altlanta or continue south to Jacksonville and pick up I-10 there. It's all about the weather.
Favorite places - if you do I-10 through Louisiana, be sure to stop in Breaux Bridge for crawfish. We stayed
here.