It depend on what you want to do with your D50. I got my D50 with the kit lens (they wont sell the body without kit lens).
I bought Nikkor VR 80-400 for birding. Very happy with the lens. I also bought Micro-Nikkor 60mm for macro photography. I use it to photograph insects and quite happy with the lens.
The kit lens is good but I have no use for 18-55 mm lens. I use it as paper weight!
The picture was taken with the D50 with Nikkor VR 80-400 handheld, no tripod.