The drive from Boston to Quebec City is only about seven hours (excluding any delays at the Derby Line border crossing), so you could do the trip in one day (I-93, I-91, A-55, A-20), with a stop for lunch in some nice New Hampshire, Vermont, or Quebec town.
But if you insist that you want to stop somewhere and rest overnight, here are a few suggestions:
The most direct route takes you through (or near) the towns of Newport (VT), Stanstead, Magog, and Sherbrooke (QC). All of these towns are smaller and would likely have a nice motel, hotel, B&B, and some decent restaurants. If you are not that fluent in French, I'd recommend stopping either in Newport (VT), or in Stanstead (QC) where they still have a higher than average English-speaking population. Magog and Sherbrooke tend to have more people who speak unilingual French, although most hotels and restaurants would likely have someone who can speak English.
Shelburne, Vermont is a nice small town just off I-89 if you were to decide to take the longer western route into Quebec via Highgate Springs or Champlain border crossings. There is a pretty large museum there with the restored "USS Ticonderoga". Just down the road a bit is the Vermont Teddy Bear Company. I'm sure you could find a nice hotel or B&B in that area that would get you a good night's sleep.
Again, if not going directly up to Quebec City, you can detour west a bit and stop at just over the halfway point in Montreal. It is a cosmopolitain city, and has several beautiful hotels and great places to eat or have a drink, or just sit on a restaurant patio (terasse) and relax to recharge your "batteries". Montreal's downtown core and main tourist areas are all bilingual, so language would not be an issue. Just be careful when you plan your trip. The June and July months tend to be very busy with festivals in Montreal area and it gets a bit harder to book rooms.