Wilde lake is known in howard county for good size crappies in the spring, you can probably land 1-2 lbers in there as I have in the past.
As far as for centennial, you would need a kayak/boat to reach some good spots. You can definately fish from shore, but there are too many bank fisherman there. There are not places you can go if you can't drive, maybe ask a friend/family to drive you? Rocky George got some decent size bass, but need an annual permit to fish there. Other places to consider is Loch Raven, which you can rent a row boat for 30 dollars a day.