What would be your suggestions for the best Orlando activities that are NOT related to the major theme parks?

We live in Florida and don't care much for the theme parks. One of the things we've enjoyed doing over the years is walking around Old Town in Kissemmee. The have lots of little shops, (not high end) and some amusement rides. Some of the big rides are as fun to watch other people go on as going on yourself. It's a fun way to spend an afternoon or evening.

what time of year?

We liked visiting the little shops in the cute quaint town of Celebration, FL, only 10 minutes or so from Disney area.

Go to Winter Park for the day and visit the Morse Gallery, which has one of the larger collections of Tiffany glass, including many huge panes that were in Tiffany's own home. Walk the streets of Winter Park, which is an older turn-of-the-century "burb" of Orlando with lots of shopping and restaurants and a terrific park. Depending on what time of year you're there, they might have their well-known art show.

Bok Tower is not too far away in Lake Wales. In addition to the Tower, there are many antique shops. The tower was hit hard by the hurricane so the results of the winds will still be obvious but they have made efforts to get the landscaping back in order, and the view from here is spectacular. Lunch at the Chalet Suzanne will be memorable for the view of the orange grove and lake from your table, as much as the surroundings inside this quaint collection of buildings (but not for the food which is pricey and not so great).

Many people make a trip to the east coast beaches or to the Cape Canaveral (or is it Kennedy?) an hour away. In Deland is DeSoto State Park where there is an old mill that's been converted to a restaurant. Your kids (?) can tube the spring-fed lake. Eat at the restaurant where your table is a grill and you do the cooking.