Stayed at the Marriott in Quincy in June and had a great time. They have a shuttle to the "T" station which is only 5 minutes away and a great way to get to downtown Boston. Only $2 each way. The Hotel was bustling but pretty new, and did a lot of wedding packages to include receptions.
If you want fresh clams go to Wollaston Beach and treat yourselves at the Clam Box. All other seafood available as well.