Good evening,
I was having some problems successfully installing the program until I realized that my DirectX was not the correct version. I had a major crash a few months back and had to reinstall from scratch and my DirectX reinstallation was one of the items I apparently forgot about.
Once I updated it to Version 9c I was off to the races.
Just wanted to say I think WWT is an awesome site and a great learning tool no matter what your age. 
I am still exploring all its features and having a ball in the process. 
Thanks and regards,
2harts4ever
" ... Nuff Said. Keep Smiling Because I'm Smiling Too!"