Hey chaps . . . need some help on M$ licensing and didn't know where else to ask.

This is the scenario

Development environment - 9 servers; which will need to be updated with the latest operating system. 3 are sql servers, 3 are COM servers (so irrelevant?), 3 are terminal servers

Development workstations
Visual Studio 6 , Visio, SQL tools (enterprise manager et al), and later the .Net dev environment. This lot for just two developers.

We currently use MSDN, but this might be a little over the top for our needs ( I don't need the vast majority of what's in the diskset for instances)

What is the best (cheapest) licensing policy that will cover all of this.