I would start out with the two inch (size 5), and two and a half (size seven). The most important thing is to match the size of your rap to the size of the forage. Here in Colorado, where the forage is small, I use even the small size 3, which is 1 and one half inches long.
I like gold, chartreuse, perch, silver blue, and orange. Don't forget the Nils Master jigging shads either. They have a fatter profile and imitate shad and small panfish better. Tip with a small minnow head, no bigger than your pinky fingernail, and simply lift once every 20 seconds, followed by pauses with shakes and jiggles.
Tyler