Please take a look at Needham!( http://www.needhamma.gov. )Its has great schools, neighborhoods, playgrounds, town center, restaurants, commuter train and a wonderful sense of community. Good Luck!
Century 21 Commonwealth
Westborough is a great town, but beware of the school system. It was very good about 6-7 years ago, not up there with a Belmont/Newton/Dover/Lincoln, etc... but very good for that part of the state. But, it has started to slide in recent years. Teachers and parents have an adversarial relationship (check out the comment section on any of the local newspapers) and I believe the teachers are starting a second year without a contract. Things are not going to get better in Westborough anytime soon. Nice town though.
I suggest looking at Hingham if your budget allows. Especially if you like to be near the ocean. Great walkable downtown and harbor area. Excellent commuter rail, bus, or ferry options to Boston. Check out the town's web site below. If you'd like a report comparing two different communities I'd be happy to prepare one for you. Just let me know which towns you'd like to compare.
As Andrew said, it will depend on your budget. Questions like these tend to bring out the salesperson in a Realtor so here goes! I work and live in Beverly on Boston's North Shore. Besides the multiple playgrounds, well funded Library and and a downtown filled with activities for both young and old, we have the added benefit of several public beaches! Both the private and business communities take great pride in keeping Beverly a Clean, Fun and Safe place to Live. Here are some links to give you a better idea of what I mean.
There are plenty of options. As Andrew noted, Winchester has a nice downtown. As do many of the "villages" of Newton, including West Newton, Nonantum, Newton Center, etc... Arlington Heights has a nice downtown, Wellesley has a great one, others I can think of are Belmont Center and Cambridge.
Winchester has a great down town area. During the summer months they have concerts on the common and a farmers market on Saturday's. The library is easily accessable and you can be in boston in a few short minutes by getting on the commuter rail that goes through the center of town. Great Community, great schools. Realistically you are looking at Sales Prices of 600,000 and up.