Thank you very much. I do have the SB600. I've been experimenting with using it and adjusting the angle etc so I'm not blinding the kids every few seconds. I haven't bumped the ISO to 800 but will give that a try. So of this is probably due to longer shutter speeds but it isn't always possible to get it that fast indoors without turning everything on. We get very diffused light indoors and have lots of trees outside so it isn't very bright. I'm off to research and see what lens I'll pick up now and what will wait for DH to "reward" me with when he comes home.
I already have couple so I want to be sure I'm not duplicating things.
ETA: I bought the 50mm f1.8 and am excited to see how that works out for me. I really appreciate your info.