Any D50 users? Please guide me!

Hi,

I use D50, and plan to keep it for, ehhh...another year or so. Currently, it is on default settings. Its limitations aside, I would like to take pictures that may be a tad sharper and focus better. I use 50mm f/1.8 and 17-55 f/2.8.

What can I do to camera settings to improve my focus? I can sharpen in PP, but focus is my major concern. If there is no way around it, I already know it will eventuallyl get better with a new body in the future. Can live with that.

Thanks.