designed to compete with the 10D, and certainly not with its successor the 20D. I can't speak for the D70, but the 20D is very easy to use.
Looking at the specs. The 20D has an 8meg sensor while the D70 is 6meg. The 20D can shoot 5 frames per second of high res jpeg while the D70 is 3fps at 'normal' res jpeg. The D70 has 5 point auto focus versus the 20d's 9 points. The 20D has a maximum ISO of 3200 to the D70s 1600.
I am novice photographer and like to take pictures of my kids playing sports. Just wondering if there is a big difference between the two and how easy they are to use.