Depending on kids ages and if they've ever been to Disney World before, this could be a tease to them. The MK monorail brings you right to the entrance of the park and kids may not understand that they can't get off with everyone else. For kids with more understanding, I think Minky's idea is great. Work in a visit to one of the monorail resorts for maybe a light lunch or snack. If you're really adventurous, you can get off the monorail at the MK entrance and walk towards the boat dock. Hop on the launch for Fort Wilderness and visit there for a little while. They have a petting zoo, pony rides and a nice buffet lunch spot. On the allearsnet.com website, Deb has all the restaurants listed for each resort and I think all three of the monorail resorts have a counter service restaurant available.
The Epcot monorail is a much longer ride and goes right over the park. If you're staying on site with a car, you'll be given a pass that entitles you to free parking at all the Disney parks. You can drive over to the TTC, park and take the Epcot monorail for the roundtrip. Otherwise, you can get a Disney bus right outside the Swan to the TTC. Another option for you would be to ride the boats around Crescent Lake. They make stops at Epcot and MGM as well as the resorts. It's less travel for you and it might be less crowded.
Tammi