Why Internet Explorer is slower than Firefox in LAN environment?

Question

I have a LAN of 213 PCs. There are following server machines:

1. MS Windows 2003 Server Standard Ed.
2. MS ISA Server 2004

Answer 1

Please explain your testing methods and results in a way that we can understand and duplicate them.

If we all find that MSIE is slower than Firefox, we can likely isolate the problem!