Dunia Fantasi, also known as Dufan, is the largest park in the Jakarta area and the only one not associated with a shopping mall. While it does look a little shabby around the edges, it nevertheless has a good set of spin rides, a giant wheel, a target shooting dark ride (rather good), a mirror maze, and two coasters. Enthusiasts would be unlikely to travel for either Halilintar (#1775) or Alap Alap (#1776), but both were running well and appeared popular with the locals. The park also appears to have a direct copy of Disney's Small World, even down to the facade, but it was under maintenance today so I couldn't review it in more detail.
One small warning for the intrepid traveller; the park has an irritating theme tune lasting around three minutes that is played on loop through speakers all over the park. Different areas have slightly different variations on it, but it's still the sort of thing that digs into the innards of your brain and slowly pushes you towards insanity. Bring earplugs!