State your lens, camera combo and type of photos/lighting you're shooting. Any combos are good.
Canon 50mm f1.8 // Canon 30D
I've been shooting a lot of family pics indoors with this lens and it is amazing. Any day that the light is low, it picks up everything. If you do your settings right, you can do almost everything with this fixed lens (and if you don't mind being proactive about moving around for the shot).