I stayed at the Hyatt Place Medford for 8 nights, with my sister and my 7month old. Although we were in Boston for a sad occasion (my grandfather's funeral) I cannot say enough good things about the high standard of this hotel. We originally choose it for the kitchenette facility in the rooms, which are great for preparing baby food. But have to say we were pleasantly surprised - our stay at hyatt place was exceptional, from the friendly, helpful staff, superb, clean rooms, delicious breakfast spread and covienient shuttle service, there is just so much that contributed to making our stay an absolute pleasure.
I highly recommend this hotel.
To add a balanced view, the only things that may not be ideal is that the hotel is not in the centre of Boston, but it's not that far away on public transport. Even better if you have a car and I think the hotel offers free parking! Also there was no room service or restaurant, so you have to pop out to get food.