Hi gilders,
Old Town is a great place to visit after the parks have closed. The car cruises take place Friday and saturday evenings. The cars start to arrive around 5pm and the car cruise down the street starts at 9pm.
The shops will be open, most stay open till around 11pm. There are quite a few fairground type rides there, ferris wheel, mini roller coaster, go karts etc, . Also there is a stage where they have live music on a weekend.
It's worth going just to see the cars. Also if you are interested Thursday night is bike night at Old Town, lots of very nice shiny Harleys to look at.
IMO there is plenty to keep you occupied. We always fit in at least one visit to Old Town while we are there.