The one drawback with the D40/X is the lack of lens motor - so it will only accept newer AFS lenses. You can surely get by, but it rules out a whole load of great lenses that could have been used - like the cheap 50mm F1.8 to the latest 10.8 fisheye and the fantastic value 80-200 F2.8 AFD.
If you don't want to get too into it, the D40 is fine - but the lack of lens motor limits the lens choices when you want to start upgrading your kit