I'll echo other comments here about a D40 and an 18-200 lens. From what I've heard the D40 is a great little camera and is lightweight and very good. The 18-200 is a great all-purpose lens and if you don't need the extra 100mm (for wildlife for example) it's the perfect travel lens.

Regarding the D60 - From what I've seen of it, don't get it. While they've increase the megapixel count, they've also lowered the base ISO from 200 to 100. It adds very little to the D40 except for cost. I'd stick with the D40 since its well established as a good camera. From what I remember, the D40x also adds very little.

I would stick with Nikon lenses (or Cannon) simply because they are generally better than the off-brand lenses and not that much more expensive. The 18-200 specifically has been very well received and a lot of people like it.