You honestly couldn't go wrong with either setup...
The D100 with the 80-400mm VR would be a great choice or maybe a 80-200mm f2.8 (one of the sharpest zooms made).
If you decide to go with the D60, a 100-400mm IS is an awesome lens, very similar to Nikkor 80-400mm, except it comes in that dreadful Canon WHITE.
Just see which package can get you more bang for your buck.
To most people, the sky is the limit. To those who love aviation, the sky is home