Thomaston Opera House offers regional, reasonably priced, productions right in western Connecticut. They have a regular Children's Theater, and we have attended 2 years of Blues Clues Live. It is definitely entertaining, and the kids love it. The actors spend time in their costumes after the production to meet and greet every kid in the audience, which is very special for the kids. Every time we pass the opera house, my daughter reminds me that Blue and Magenta "live" there. :) They have a production of Rugrats coming up in Fall 2010: October 16, 17, 23 & 24, 2010 at 1:00pm & 4:00pm. They have a little shop in the back of the theater that had little gifts related to the show, and then lots of other toys, etc. They also sold both sugary and healthy snack choices at a concession, both at intermission and after the show.
I have also had the pleasure of attending adult performances, as well as dance recitals in this space. It is handicapped accessible. You need to enter through the back, however, and take the elevator up through the Town Hall/Police Department. It is comfortable for those who use a wheelchair, and the staff is accommodating. You can purchase tickets online and have them mailed to your home, or you can pick them up in the box office 30 minutes before the performance. Definitely a good place to introduce children to the performing arts!