Using the kit lens from the D40 on the D50 is not a problem. As for the shutter problem on the D50, that may not be a camera fault; it depends on what you are/were doing.
Hi . . .
I have a Nikon D40 with the lens it came with. Is it compatible with the D50?
I ask because I became aware that the D40 had a new system regarding lenses with an integrated motor for autofocus.
Basically, my camera broke, and I borrowed my sister's D50, and then that broke - the shutter stuck until pressing the button again. I'm of the opinion that it was gonna happen no matter who was using it, but doing some research made be discover a possible incompatibility that could be my fault.
Thanks for your advice/opinions!